Search

A charring behavior was found during the combustion of para-aramid chopped fibers/polyphenylene sulfide (ACFs/PPS) composite paper, which formed a highly graphitized carbon layer structure with specific mechanical properties. This sturdy structure is composed of a dense carbon layer mixed evenly between the inner and outer layers, the outer layer can effectively block the spread of oxygen and degradation products, as well as external heat radiation, while safeguarding the inner layer's structural integrity. Herein, we systematically researched the flame retardancy and thermal degradation properties of ACFs/PPS composite paper. In combustion testing, the char of ACFs/PPS composite paper could support a weight of 50 g, while the neat aramid paper was burned through by fire, which indicates the Charcoal-forming property of ACFs/PPS composite paper is better than that of neat aramid paper, and ACFs/PPS composite paper has better fire resistance because of its good char formation. Meanwhile, we further showcase the application in electrically insulating and firefighting clothing interlayers. This study has revealed a distinct charring behavior during the combustion of ACFs/PPS composite paper. The combustion, thermal degradation, fireproofing, and flame retardancy of ACFs/PPS were all thoroughly researched. The PPS has a considerable impact on the production of a more compact char layer in a condensed phase on the aramid surface during combustion. This structure maximum extent to ensure the structural integrity of ACFs and form residual carbon with certain mechanical properties. At the same time, the carbon structure has good flame and fire resistance. In addition, ACFs/PPS composite paper has the advantages of being lightweight and flexible, which indicates that it has great flexibility in demand. This kind of aramid composite paper with good flame retardant, fireproofing, and heat insulation properties provides a feasible way to be used as the interlayer of firefighting clothing and electrically insulating materials. [Display omitted] • Adding PPS greatly improve the flame retardancy and char yield of aramid paper. • Highly graphitization char layer was formed during the combustion of ACFs/PPS composite paper. • ACFs/PPS composite paper showcase the application in electrically insulating and firefighting clothing interlayer. [ABSTRACT FROM AUTHOR]

The extent to which pre-Columbian human societies occupied and significantly impacted Amazonian environments have been long-standing questions and are currently under active discussion. Data are particularly limited from terra firme forests, formations away from watercourses that occupy over 90 % of the Amazon Basin. This paper investigates pre-Columbian influences on fire and vegetation in three regions of the western Peruvian Amazon through phytolith and charcoal analysis of terrestrial soils. One region in the Tapiche-Blanco watersheds was not previously studied. In the other two regions, the Los Amigos Biological Station and between the towns of Iquitos and Nauta, previous phytolith research was expanded to study in more detail forest composition and cultural palm usage through time. Our results indicate the diverse forests in these regions remained intact and were little affected by human forest clearing and agriculture with annual seed and root crops during the past 2000–5000 years of prehistory. Cultural palm enrichment is indicated in limited areas within each region studied, and usually occurred in riverine environments. The accumulated evidence from a number of different proxies indicates the persistence of diverse, forest-dominated pre-Columbian landscapes in western and parts of central Amazonia studied to date. [ABSTRACT FROM AUTHOR]

In the framework of the NWO project "What went into the melting pot? Land-use, agriculture, and craft production as indicators for the contributions of Greek migrants and local inhabitants to the so-called Greek colonization in Italy (ca. 850–550 BC)", science-based methods are employed to analyze and compare the organization of subsistence strategies in the Greek motherland and in the indigenous and colonial milieus of Italy (Crielaard et al. 2020). As a part of the subproject 'Flora & Fauna', which focuses on farming practices, subsistence strategies and surplus production, Iron Age material from the settlement of Krania in the Pieria region of Greece was analyzed. The site was excavated in 2001 and revealed occupation phases from the 3rd millennium BC to the Hellenistic period. The amount of ceramics recovered demonstrates the importance of trade with the rest of Greece, in particular Corinth, providing evidence for long-standing contacts and networks. Two pit structures contained a high concentration of material, notably charcoal and ceramics dating to the 9th-8th centuries BC. This material constitutes an interesting case study in itself but also as a regional comparandum with other Greek assemblages. This paper discusses how anthracological analysis can contribute to our understanding of human-environment interactions, anthropogenic practices and environmental management. [ABSTRACT FROM AUTHOR]

The paper deals with an overview of early anthropogenic impact on the landscapes of the southeastern Baltic region and is based on the results of palaeolimnological and archaeological studies carried out on the Vishtynets Upland, Kaliningrad oblast, Russian Federation. The detailed study of available palynological (including microcharcoal), geochemical and archaeological data has revealed possible signs of anthropogenic impact on the landscape from the Early Mesolithic to the Middle Ages, while the results of lithological, geochronological and diatom analyses provided a basis for a better understanding of natural processes. Palynological data have shown that the first signs of human impact on landscapes date back to the Early Mesolithic (approximately from 10,000 cal yr. BP), indicating the existence of local deforested areas. The presence of pollen from plantindicators of open habitats and pastures, as well as Pteridium and Corylus , combined with elevated Ba and Sr values as indicators of burning, suggests the deliberate burning of forests for the enhancement of hunting and mobility, as well as for the propagation of edible plants. The correlation of microcharcoal and pollen data has revealed several peaks of human activity in the Neolithic and showed that cultivation of Cerealia on the Vishtynets Upland began during this period (5120 - 4000 cal yr. BP). The first signs of metallurgy in the region emerged in the period 4500–3000 cal yr. BP (the late Neolithic – the Bronze Age) and are indicated by the simultaneous growth of V, Pb, Ni, Zn, As, Fe 2 O 3 and microcharcoal curves. [ABSTRACT FROM AUTHOR]

COVID-19 severely impacted small industries in Indonesia and many collapsed. Sustainable education is essential to help small industries recover post-pandemic through an open innovation design program to improve small industries' economic, social, and environmental performance. This paper examined the impacts of the sustainable education program implemented and explored open innovations suitable for the sustainability of small industries in developing countries, such as Indonesia, after the pandemic. This research employed a Participatory Action Research (PAR) approach involving academics, government, the community, and four small industries in West Java, Indonesia. Our findings reveal that the sustainable education program through learning activities and direct practice provides valuable knowledge and experience for small industries in designing economic, social, and environmental innovations. Open innovations post-pandemic suitable for small industries in Indonesia include simple business digitalization for company economic growth, the recruitment of people losing their jobs due to the pandemic to achieve social benefits, and innovations in using environmentally friendly packaging and charcoal briquette fuel as an environmental awareness effort. This study recommends that the open innovation designed for small industries be right on target and done using a participatory method to achieve sustainability after the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

[Display omitted] • Construction of DSSCs electrodes (P25/BC photoanode and MBCF counter electrode). • In DSSCs, the PCE of P25/BC-Pt (6.27%) is much higher than that of Pure P25-Pt (4.96%). • MBCF shows good catalytic activity of for I 3 − behaving high PCE of P25/BC-MBCF. • Our work aims to provide a simple-green way to prepare bamboo charcoal-based DSSCs. Bamboo charcoal (BC)-doped titanium dioxide (P25/BC) and modified BC (MBC) loaded with Fe 3 O 4 (MBCF) were used as double electrodes to improve the power conversion efficiency (PCE) of a dye-sensitized solar cell (DSCC). BC was doped into the P25 photoanode, and P25 improved dye adsorption and reduced the transfer impedance of photogenerated electrons. The PCE of P25-Pt (4.96%) was 6.27% higher than that of P25/BC-Pt. MBC contained more structural defects, and the oxygen-containing reactive groups generated on its surface combined with Fe3+ ions, resulting in a uniform loading of Fe 3 O 4 on MBC. The high electrocatalytic performance of Fe 3 O 4 with the abundant structural defects of MBC reduced the charge transfer resistance and provided fast electron transfer paths, giving MBCF good electrical conductivity and electrocatalytic activity. DSSCs assembled using the P25/BC photoanodes and MBCF-2 CE showed a PCE of 4.27%. Electrochemical performance tests of MBCF-2 showed a specific capacitance of 150 F/g at 1 A/g and capacitance retention of 91.1% after 5000 cycles. The results demonstrate that BC has potential electrocatalytic and energy storage applications, and this paper provides a feasible strategy for applying biomass carbon-based materials in DSSCs. [ABSTRACT FROM AUTHOR]

• A biochar gel was designed by combining alginate with biochar. • DFT calculation predicted that alginate can improve the adsorption performance of biochar. • MD simulation predicts that biochar can improve the reusability of alginate gel. • Biochar/alginate composite gel was synthesized by compounding activated platanus acerifolia leaf charcoal with alginate, and the experimental results achieved the expectations of the simulation. In this paper, activated biochar and alginate are combined to form gel for the removal of Pb(II) in water. This composite not only improves the adsorption performance of biochar for Pb(II), avoiding the drawback of difficult recovery of biochar but also enhances the structural stability of alginate gel in the recycling process by utilizing biochar. The adsorption mechanism of Pb(II) on functional group-modified carbon and alginate structures, as well as the structural stability of the adsorbent, were observed using density functional theory (DFT) and molecular dynamics (MD) simulations. The results indicate that the adsorption of carboxyl groups to Pb(II) is stronger than that of hydroxyl groups, and the adsorption performance of alginate is stronger than that of carbon. Carbon improves the stability of the composite adsorbent. The biochar/alginate composite gel was synthesized by compounding activated platanus acerifolia leaf charcoal with alginate and was used in the experiment of removing Pb(II) from water. The experimental results achieved the expectations of the simulation. The adsorption isotherms and kinetic data were analyzed and fitted. The results indicate that the adsorption isotherms conform to the Langmuir model, and the adsorption kinetics follow pseudo-second-order adsorption. [ABSTRACT FROM AUTHOR]

Densification and torrefaction are potential technologies to valorize lignocellulosic residues into cleaner and sustainable alternative energy carriers for domestic, institutional, commercial and industrial thermal energy applications. Therefore, this review paper has focused on sources of lignocellulosic biomass for energy production. Furthermore, the processes involved in production of raw and torrefied briquettes/pellets have been discussed. Additionally, the physicomechanical, emissions and combustion properties of raw and torrefied briquettes produced from lignocellulosic residues have been presented. Also, the economics of briquetting lignocellulosic biomass materials have also been reviewed. The quality of densified solid biomass fuels from lignocellulosic residues was found to dependent on the feedstock and pretreatment conditions. Additionally, torrefaction and densification have been reported to upgrade the energy properties of loose biomass materials, as potential alternative fuel to firewood and charcoal. Finally, the economic profitability of densification projects has been found to be dependent on the availability of feedstocks, technology used and market potential of the product. [ABSTRACT FROM AUTHOR]

This paper presents the results of the wood charcoal analyses from the Middle Paleolithic open-air site at Nesher Ramla, on the central coastal plain of Israel. The study focuses on the interpretation of the charcoals left by fires used by Middle Paleolithic hominins during early Marine Isotope Stage (MIS) 5. Moreover, this study sheds light on the arboreal taxa present in the vegetation and environmental conditions in the southern Levant during the Middle Paleolithic. A small quantity of identifiable charcoals was retrieved from the 8-m-thick archaeological sequence of the site (Units II to VI). The largest charcoal assemblage was recovered from part of the sequence dated to MIS 5e. The results show the presence of deciduous Quercus sp. and Prunus. The presence of these taxa, together with other proxies from the multidisciplinary studies at Nesher Ramla, indicate an arboreal setting with relatively humid and mild climatic conditions in MIS 5e. Our results further suggest that wood was used as fuel at Nesher Ramla. Given the scarcity of Middle Paleolithic sites in the Levant that have yielded charcoal, this new data from Nesher Ramla constitutes an important contribution to the study of past environments and the exploitation of plant resources by human groups. [ABSTRACT FROM AUTHOR]

This paper presents the first insight into the interpretation of the wood charcoal from the Holocene layers of Wonderwerk Cave. Situated in the Northern Cape Province in the arid interior of South Africa, the site provides a unique and valuable chronological record of past environmental fluctuations and responding human behavioural adaptations spanning the last two million years. The Holocene strata have been dated to cover the last 12.5 ka cal BP years, but exclude the last 100 years because of contamination. A sizeable amount of charcoal was recovered from these strata and remnants have been identified, described and the species composition amongst the strata compared. Most identified species are those that tolerate hot, dry conditions, signalling an arid trend during the Holocene. Comparison with present day species distributions suggests an eastwards shift in modern vegetation. The charcoal data also indicate that during the mid Holocene there was a wetter period from 6.2 to 4.5 ka cal BP, coinciding with stratum 4a. [ABSTRACT FROM AUTHOR]

Recent research on Later Stone Age (LSA) San rock art in southern Africa has unveiled some of the paint recipes the artists employed. However, these discoveries still need to be linked to human activities in or near the rock shelters where the paintings were made. In this paper, we report characterization and dating results from the catchment of the Metolong Dam, Phuthiatsana Valley, Lesotho. A total of 92 rock painting samples, six grindstones with traces of colouring materials from an excavated context, and 17 potential raw colouring materials were studied. We identified three previously unreported ingredients used by the artists: manganese oxides, calcined bones, and soot. Grindstones are stained with the same raw materials that the painters used. We propose that one of them may have served to prepare the red pigment used to make a human figure and a bichrome eland at Ha Makotoko, but direct links remain difficult to establish with certainty. The potential colouring materials in the valley are red clays, white clays (kaolinite and illite-or-montmorillonite), and gypsum, three compounds used as paints by the artists. Tests conducted to verify their suitability for paintings show these materials may have been ground, but settling (after pre-grinding) offers a quicker and easier way to obtain a fine powder as observed in the paints. Finally, 12 AMS dates provide an initial framework for studying the changing use of paint recipes in the Phuthiatsana Valley over time. Charcoal appears to have been employed over a period of at least 3000 years and carbon black for at least 2000 years, with soot seemingly used only before 2000 cal. BP. This study is currently the largest characterization and dating study of LSA rock art in southern Africa and shows the potential that such combined investigations offer for linking excavated and parietal components of the region's hunter-gatherer archaeological record. [ABSTRACT FROM AUTHOR]

Brazil is the world's leading charcoal producer, mainly used as an energy source and reducing agent for iron ore in the pig iron and steel industry. Despite its vast production, much of the Brazilian charcoal production remains low-tech and inefficient, with limited utilization of by-products. To address potential environmental impacts, promote a circular economy, and reduce energy waste in the charcoal production chain, this study presents the benefits of using wood carbonization by-products through a Life Cycle Assessment (LCA). The analysis was performed by comparing four scenarios: i) Current wood carbonization; ii) Wood carbonization with combustion of non-condensable gases; iii) Wood carbonization with energy recovering of non-condensable gases for electricity generation; and iv) Assessing the utilization of insoluble tar and biomass waste for generating additional electricity, and the use of Pyroligneous Extract (PE) in eucalyptus cultivation. The results demonstrate that by-product utilization prevents energy waste, with an estimated potential to generate 0.19–0.26 MWh per ton of charcoal in Scenarios 3 and 4. Furthermore, 3.3 t of CO2 eq./t of charcoal are sequestered from the atmosphere, and Scenarios 2, 3, and 4 can increase this amount by 5.06%, 6.7%, and 0.48%, respectively. This paper introduces an innovative assessment of PE utilization during eucalyptus cultivation, resulting in a 6.16% reduction in greenhouse gas emission and a 46.98% decrease in abiotic resource consumption, attributed to PE's potential to partially reduce pesticide consumption. [Display omitted] • Photochemical Oxidation is the main impact category due to CO emissions in carbonization kilns. • Potential to generate 0.19–0.26 MWh of electricity per ton of charcoal through by-products utilization. • Forest residues and insoluble tar increase electricity generation potential by 36%. • Charcoal by-products offset GHG emissions from 14 to 203 kg/ton of charcoal. • Pyroligneous Extract use leads to 6% lower GHG emissions and 47% decrease in abiotic resource consumption. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mixing energy concept was well suited for development of formulations with similar composition but giving different fine particle fractions when dosed with Easyhaler. • Developed Inda/Glyco formulations were suitable for comparison of pharmacokinetic (PK) behavior with the reference product Ultibro Breezhaler. • For both active substances there were clear differences in plasma concentration profiles between the test products. • For Inda, Easyhaler formulation B was bioequivalent to the reference. For Glyco, none of the test formulations were fully equivalent. • Additional tools can be envisaged to tune the performance of the two APIs to fully match the reference product. This paper describes the development of a fixed dose dry powder combination of indacaterol maleate (Inda) and glycopyrronium bromide (Glyco) in Easyhaler® inhaler for a comparative pharmacokinetic (PK) study, as well as the outcome of such a study. The development aim was to produce formulations with three different in vitro dispersibility profiles for both Inda and Glyco. This so-called 'rake' approach allows for quantitation of the candidate formulations relative to the reference product Ultibro® Breezhaler® in terms of the key PK parameters. Three formulations (A, B and C) were produced based on the mixing energy concept. For both APIs, formulation A (lowest mixing energy) displayed the highest fine particle fractions and formulation C (highest mixing energy) the lowest. GMP manufacturing confirmed the performance of the three formulations. The candidate formulations were tested against the reference product in a single dose PK study in healthy volunteers. Clear differences in Inda plasma concentration profiles were observed between the treatments when administered concomitantly with charcoal, with Easyhaler A showing the highest C max value and Easyhaler C the lowest. Easyhaler B was bioequivalent to Ultibro Breezhaler with regard to the primary PK parameters of Inda, C max and AUC 72h. For Glyco, Easyhaler formulations A, B and C provided lower peak concentrations than Ultibro Breezhaler. For AUC 72h of Glyco , Easyhaler B was bioequivalent to the reference product. Additional measures for adjustment of formulation performance can be foreseen, whose effects can be predicted based on mixing energy theory. [ABSTRACT FROM AUTHOR]

The recovery and identification of wood charcoals from soil not associated to archaeological excavation is called pedoanthracology. Researchers in this field use different sampling methods, and only one study, in a temperate context, has compared their efficiency so far. In this paper, we compare the efficiency of three sampling methods on charcoal concentration (>4 mm) and on taxonomic representativeness in a tropical environment for the first time. These methods are pit sampling, auger sampling and opportunistic handpicking of charcoal on tree uprooting mounds or in the soil excavated during the digging of a pit. Our results suggest that the two digging methods (pit and auger) allow to recover similar charcoal concentrations whatever the site and the depth under consideration. But as expected, the charcoal concentration of a site depends on its history (e.g. type of activity). We also show that the estimation of the minimal sampling effort required to obtain taxonomically representative assemblages, in terms of number of charcoals and of auger samplings, varied greatly depending on the site and on the presence of overrepresented taxa. Finally, our results show that auger cores were often monospecific (34%). Nevertheless, they allowed to recover different taxa from the pit method, with 18–21% of the taxa exclusive to the first method and 30–40% of the taxa exclusive to the second one in the sites under consideration. Charcoals from opportunistic handpicking also allowed to improve the taxonomic diversity of the whole assemblage of a site with 5–15% of the taxa being exclusive to this method. The three methods are therefore complementary and we suggest to use the three of them to obtain the best taxonomic diversity in an anthracological assemblage and to overcome the specific biases of each method. With this study, we hope that we will help tropical (pedo)anthracologists to optimize charcoal sampling in anthropogenic sites were the sampling design cannot benefit from archaeological excavations. [ABSTRACT FROM AUTHOR]

Numerous charcoal kiln remains can still be found throughout the world, evidencing wood harvesting related to former industries. These remains represent effective sources and tools for studying (i) pre-industrial pressures on forest resources and (ii) past strategies related to woodland management. However, radiocarbon dating (AMS), which is the main tool to reconstruct the chronology of past charcoal manufacturing activity, doesn't provide sufficiently accurate dating, especially for the post-1650 period, due to the broad probability range of the dates resulting from wiggles in the calibration curve. In order to overcome the radiocarbon dating limitation and therefore refine the chronology of modern charcoal manufacturing, this paper proposes to apply an integrated approach combining archaeology, micromorphology, anthracology and dendrochronology. To characterise the archaeological record of a target charcoal kiln terrace from the "Forêt de Bernadouze", located in a historical iron production valley of the Northern Pyrenees, we combined classical stratigraphic analysis with a micromorphological study. The results highlight the multiperiod nature of the terrace, i.e. a palimpsest of multiple charcoal production episodes, revealing two major phases marked by an abandonment period between them. Subsequently, we constructed a beech charcoal-ring (n = 49) chronology cross-dated with the new "Forêt de Bernadouze" reference chronology from freshly felled, living beech trees (n = 24) to obtain the annual resolution of charcoal ring formation. Based on the new reconstructed master chronology covering the 1879–2016 period, we were able to calibrate the charcoal-ring chronology for the 1881–1941 period. Consequently, we (i) dated the charcoal production activity performed on the target terrace during the 1924–1942 period and (ii) identified a shift in the rate of use of the terrace, from one-off to high-intensive use. This study also provides new insights regarding (i) the particular nature of the archaeological record and (ii) the operating and timing of past charcoal-making practices in connection with silvicultural treatments. [ABSTRACT FROM AUTHOR]

In this paper, the first results of charcoal analyses carried out at Cova des Moro (Manacor, Mallorca, Spain) are presented. This cave is an archaeological but also palaeontological site that provides information on endemic fauna (the extinct caprine Myotragus balearicus) before the arrival of humans and, later, the relationship between the first farmers and the landscape. Several human occupations in the cave have been documented, from the Chalcolithic (end of the 3rd millennium cal BC), the Bronze Age (2nd millennium cal BC) and, finally, the Almohad period (13th century AD), during which the cave was used for different purposes. The first results of charcoal analyses at Cova des Moro provide information about the natural plant communities exploited by humans for comparison with later sequences, enabling us to evaluate how humans managed this territory over time. The results point to the exploitation of Mediterranean woodlands with wild olive (Olea europaea), mastic (Pistacia lentiscus), green olive tree (Phillyrea), Aleppo pine (Pinus halepensis), rosemary (Rosmarinus officinalis), juniper (Juniperus) and rockrose species (Cistus), among others; these taxa would become the main elements of Mallorca's coastal landscape in later times, and it has been proven that they would already have been present as the island's natural flora at the time humans arrived there. [ABSTRACT FROM AUTHOR]

This paper provides a critical review of the main methodological achievements in sampling and quantitative analysis in anthracology, the study of wood charcoal macro-remains from archaeological contexts. The application of appropriate sampling protocols is a prerequisite for the study of all types of archaeo-anthracological assemblages, particularly when it comes to the study of wood fuel waste. Sampling directly impacts the quantitative taxonomic composition of a charcoal assemblage and its representativeness with regard to reconstructing ancient woodland composition. The selection of contexts and deposits appropriate for this purpose, the spatial sampling of charcoal scatters, sieving methods and mesh size, what constitutes optimal sample size and the outcomes of charcoal fragmentation, are all discussed. Provided that appropriate methods are followed, the case for the palaeoecological representativeness of archaeo-anthracological fuel waste deposits is argued in detail. This also includes a discussion of the contribution of laboratory experiments to understanding the impacts of combustion and post-depositional processes on archaeological charcoal preservation and the implications of fuelwood properties for wood collection. We argue that ancient firewood use was predicated principally on wood availability in past vegetation and its interdependence with ancient landscape management practices. Lastly, we discuss the application of multivariate methods in anthracology, and the insights they may provide for reconstructing archaeological charcoal taphonomy, and past woodland vegetation and fuel uses. [ABSTRACT FROM AUTHOR]

Previous methodological developments in the field of anthracology have led to the definition of rigorous sampling methods in archaeological contexts, which provide highly accurate and reliable taxonomic frequency spectra as a basis for understanding past woodland vegetation. However, the fuelwood taxon frequency spectra represent a synthetic picture of forest composition in the environs of an archaeological site. Our aim in this paper is to describe the heterogeneity of woodland distribution. The Abeurador cave (Hérault) in the south of France, has previously provided an exceptionally rich palaeoecological study. We further explore the spatial frequency distributions of the charcoal taxa found in charcoal scatters from two layers dated to the Mesolithic (Preboreal). The frequencies of abundant taxa have a unimodal distribution in the sampled grid squares, close to the normal distribution. The ratio s2/m (variance/mean) termed the 'distribution index', estimates the regularity of distribution of each taxon in the grid squares. We hypothesized that the frequency distribution of a taxon in a layer could be considered to be its statistical sampling distribution (i.e. probability distribution) in the firewood collection catchment at a given time, since the quantity of this taxon fluctuates in each firewood assemblage according to its probability of collection, relating to its distribution heterogeneity (or accessibility) in the past environment. The distribution index was then used to estimate the heterogeneity of the palaeoenvironmental distribution of each taxon and thus its random, uniform or clustered distribution. On this basis, we propose a mapped restitution of the evolution of the main woodland species in the surroundings of the Abeurador during the Early Holocene, integrated with the whole sequence dynamics. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the Sibudu Cave habitat that is dated to the late Pleistocene using archaeological wood charcoal, in order to reconstruct the environment and the activity of the people who interacted with the landscape. Standard anthracology procedures were applied in this qualitative study to analyse charcoal remains from the cave. A representative subset of charcoal remains was subsampled from a larger assemblage and environmental data, as well as evidence of wood use, are interpreted from 72 charcoal types that include 42 types that we identified taxonomically. We highlight that the environment at Sibudu supported a multi-layered Forest with Savanna vegetation based on the presence of many important taxa of these vegetation communities. The wood of the identified taxa has much rot fungi and was also burrowed by pests; however, it is not possible to infer at this stage if the fungi seen here were pathogenic. The presence of fungi is indicative of an environmental setting with high humidity and warm temperatures, such as is optimal for these types of fungi to flourish. Climatic conditions interpreted here agree with previous interpretations that were made from other environmental proxies. These conditions were only intense enough to disturb the microhabitat at Sibudu and did not change the vegetation near the cave. Also noted during the analysis, is that burning wood logs that were infected with brown rot consistently from c.73 to 72 ka probably produced very warm fires. [ABSTRACT FROM AUTHOR]

Analysis of charcoal particles preserved in lake sediments has been frequently used to reconstruct fire, vegetation and climate history. Larger macroscopic particles (>125 μm) are attributed to local fires, whereas microscopic charcoal particles (<125 μm), observed on pollen slides, are a signal of regional fire. Taxonomic identification of the charcoal particles adds to the fire-history reconstruction by providing information about fuel composition and past fire conditions. Identification of charcoal can unravel one of the longstanding questions regarding past fire regimes, namely what was burning. This paper describes an analysis of charcoal particles preserved in the sediments of a small closed-basin lake in Yellowstone National Park. Blacktail Pond (44.954°N, 110.604°W; 2012 m elev) is located in steppe vegetation surrounded by conifer forest. Previous studies of the site have presented a multi-proxy environmental history of the last 14,650 years. The focus of this investigation was on the fire history of the early-Holocene (11,500–9900 cal yr BP). Thirty-nine sediment samples were taken at 0.5 cm intervals to examine macroscopic charcoal particles, with attention on two large charcoal peaks at 10,970 and 10,200 cal yr BP that registered large or near-site fires. Twenty-eight samples contained 243 large-enough particles (180–250 μm) to be examined with scanning electron microscopy. We were able to identify charcoal of conifers (Pinus , Picea, and Abies or Juniperus), Artemisia and unidentified deciduous shrubs, and unidentified monocotyledons. The first fire burned a mixture of fuels, whereas the second episode burned Artemisia , shrubs and herbs but no conifers. The results are consistent with previous pollen interpretations at Blacktail Pond that indicate an open mixed-conifer forest in the early Holocene prior to 10,750 cal yr BP, replaced by Pinus contorta forest on the slopes and steppe in the valley. The relative dominance of Pinus contorta -type charcoal points to the importance of fire as a catalyst for the spread of this species. [ABSTRACT FROM AUTHOR]

To improve the efficiency and safety of the thermochemical conversion process of lignin residues from the bamboo paper factory, the residual lignin of black liquor was precipitated by concentrated hydrochloric acid. It was further washed using a hydrochloric acid solution with a pH of 2 and deionized water to obtain lignin samples. The ash of lignin samples with different washing processes was prepared using a muffle furnace according to standard method (GB/T 36057-2018). Their surface morphology, chemical compositions and thermochemical behaviors were investigated by cold field emission scanning electron microscope, X-ray fluorescence analyzer, X-ray diffractometer, and synchronous thermal analysis. The results showed that the washing process changed the type and content of chemical compositions in lignin ash and affected its thermochemical behaviors. The ash content of L 1 sample (13.76%) decreased to 6.13% (L 2 sample) and 4.35% (L 3 sample) when the pH value of washing filter was 4 and 7. The efficiency of ash removal was 68.39%. The LA 1 sample was composed of Si, S, O, Na, Cl, K, Ni, Zr, and Pd, especially for Cl (46.49%) and K (41.85%). The washing process decreased Cl and K. LA 2 and LA 3 samples had the high content of Si, S and O. This increased the R a and F, and deceased R b , R b/a , R b/(a+p) , F u , and S/A. Three weight loss peaks of the DTG curve and three prominent endothermic peaks of the DSC curve corresponded to Cl release, Na and K release, and S release for LA 1 sample. Compared with LA 1 , LA 2 , and LA 3 had a slight weight loss. The washing process increased the efficiency and safety of the thermochemical conversion of lignin residues in the bamboo papermaking factory. • Washing process changes chemical compositions and thermochemical behaviors of lignin ash. • Ash content of L1 sample (13.76%) decreases to 6.13% of L2 sample and 4.35% of L3 sample. • LA1 sample includes Si, S, O, Na, Cl, K, Ni, Zr, and Pd, especially for 46.49% of Cl and 41.85% of K. • Washing process improves fusion properties of ash due to removal of Cl and K. • The Cl release, Na and K release, and S release lead to weight loss of LA1 sample. [ABSTRACT FROM AUTHOR]

• We present a novel integration for reducing CO 2 emissions in blast furnaces. • It combines top gas recycling, oxy-fuel regime, power to gas and biomass pyrolysis. • The integration was modelled using the extended operating line methodology. • The best performance was found for pyrolysis at 700 °C. • The CO 2 emissions were reduced by 58% (9.8 MJ/kg CO2 energy consumption) The paper introduces a novel approach for mitigating CO 2 emissions in blast furnaces by integrating top gas recycling, an oxy-fuel regime, power to gas, and biomass pyrolysis. Various case studies were conducted, involving the adjustment of pyrolysis temperatures (300 °C, 500 °C, 700 °C, and 900 °C) and varying the quantity of blast furnace gas directed to methanation for carbon recycling. Pinus radiata, abundant and cost-effective in Chile and Spain, was chosen as the biomass source. The integration was modeled using the extended operating line methodology and evaluated through 12 key performance indicators, such as flame temperature, coke consumption, CO 2 emissions, and specific primary energy consumption per unit of CO 2 avoided. Optimal performance was observed with pyrolysis at 700 °C and no blast furnace gas recycled through methanation. This configuration achieved a 58 % reduction in CO 2 emissions, with an energy consumption of 9.8 MJ/kg CO2 , and obviated the need for geological storage. Comparing this innovative proposal with other oxygen blast furnace approaches from the literature revealed a 13 percentage point improvement in CO 2 reduction over the second-best alternative. Additionally, the required electrolysis capacity, influencing capital expenditure, was 57 % lower, and energy consumption was reduced by 44 %. [ABSTRACT FROM AUTHOR]

Injecting new fuels like charcoal and semicoke into ironmaking blast furnaces (BF) helps reduce pulverized coal and coke consumption, leading to significant environmental and economic benefits. This paper comprehensively assesses the performance of blast furnace with the injection of charcoal, semicoke, or pulverized coal. For this purpose, a recently integrated BF model that simulates the whole BF below the burden surface in terms of the gas-solid-liquid-powder multiphase reacting flows is extended to simulate the application of charcoal and semicoke injection. The combustion characteristics of charcoal, semicoke, and pulverized coal in raceways are first revealed. Then, the effects of the combustion on the in-furnace states and overall BF performances are compared in detail. The results show that the overall BF performance in terms of gas flame temperature, coke rate, and hot metal temperature is susceptible to specific components in the injected fuels, including moisture content and fixed carbon ratio. A lower moisture and a higher fixed carbon ratio result in a higher gas flame temperature and fuel-coal replacement ratio and thus a lower coke rate. Overall, the charcoal and semicoke injection is feasible, however, subject to approximate pre-treatment. This integrated BF model can offer a cost-effective way to explore the injection of new fuels of various types to reduce carbon dioxide emissions. [Display omitted] • The complex gas-solid-liquid-power multiphase reacting flow in BF is simulated. • Particle combustion, gas-solid/liquid, and liquid-solid interactions are included. • The same modeling approach can be extended to other types of coal-like fuels. • Effects of coal-like fuel injection on BF inner thermochemical states are studied. • The specific requirements of the injectant's component are discussed. [ABSTRACT FROM AUTHOR]

The paper presents characterization of chicken manure and mixture of chicken manure (CM) and beech wood (WB) carbonization at 450 and 600 °C. Experiments were carried out in small scale batch reactor. The obtained results indicate that increase in the amount of beech wood in the pellets caused increase in fixed carbon content and also affected increase in the calorific value of biochar. The results show that biochar obtained in the carbonization process of chicken manure cannot be used for the barbecue charcoal production, which is caused by low C fix and high ash content. Because of this, adding wood may be a good solution for the carbonization process. Experimental investigation showed that carbonization of pellets consisting of CM50 % and CM25 % lead to obtained biochar which meets standards for briquette barbecue production. Experimental results showed the possibility of using pyrolysis gases for energy purposes. Carbonization in different temperatures lead to production of pyrolysis gas mixtures with calorific value higher than the energy demand of the process. Moreover obtained energy contained in gases can cover the part of the heat demand of the farm. Analysis of heavy metals content showed that biochars meet the standards defined by the International Biochar Initiative. [ABSTRACT FROM AUTHOR]

Understanding human impact on the vegetation of the Tibetan Plateau through the Holocene is important for developing strategies for sustainable ecosystem management in the region. In this paper, 53 pairs of surface-soil samples from inside and outside livestock enclosures were obtained from across the Tibetan Plateau to investigate the differences in pollen assemblages between grazed and ungrazed sites. This modern dataset was then applied to palynological records from four lakes in the northeast Tibetan Plateau region to investigate middle to late Holocene grazing history. Results show that modern grazing activities have a limited impact on the vegetation, although grazing activity leads to an increase in the pollen proportion of Cyperaceae, Artemisia , Ranunculaceae, Brassicaceae, Taraxacum -type, Fabaceae, and Saxifrageceae while representatives of Poaceae, Chenopodiaceae, and Aster -type pollen decrease. Application of these grazing indicators to the pollen spectra obtained from the four lake sites, together with other proxies, reveals that grazing activity only commenced during the last few hundred years in the northeast marginal areas of the Tibetan Plateau at c. 3000 m a.s.l, while there is no grazing signal in pollen records from above 4000 m a.s.l. Our study emphasises the importance of using multi-proxy methods in estimating signals of past human activity. • Pollen assemblage should be insensitive to grazing activities on the Tibetan Plateau. • Human impacts on vegetation at ∼3400 m a.s.l are limited to within a few centuries. • No significant pollen signal of grazing is revealed for the high-elevation areas. [ABSTRACT FROM AUTHOR]

Grapevine and wine have deeply shaped the landscapes, economy and cultures of Europe and the Mediterranean. In France, it is considered that viticulture started in the south via contacts with Mediterranean populations (Greeks, Etruscans, Phoenicians), during the second half of the 1st millennium BCE, and spread further with the Romans. Wild grapevines were nevertheless present in various areas of the country all through the Holocene. No archaeological or historical source allows us to follow the history of grapevine and viticulture over the entire Holocene period and over the whole territory. In this paper we investigate the potential of archaeological plant macroremains (seed/fruits and wood) to trace the history of the vine on a large scale. We have assembled the largest possible database of published and unpublished archaeobotanical data, comprising 4449 site-phases for seed and fruits and 1356 site-phases for wood remains. In spite of taphonomic discrepancies and imbalances in the datasets, the different types of macroremains and modes of preservation produce consistent patterns. They provide the first comprehensive picture of the spread of grapevine, fluctuations in the economic role of viticulture and grape uses over time, although some periods and regions are less documented. Grapevine remains are regularly recorded from the Mesolithic to the Iron Age in most regions showing that human societies were already familiar with the wild plant and its fruits, especially in the Mediterranean. In this region, Vitis remains become considerably more frequent and numerous during the Iron Age, from around 500 BCE onwards, testifying to the rapid and strong implantation of viticulture. Grapevine macroremains confirm that the spread of viticulture outside the Mediterranean area occurred mainly during the Roman period. However, this expansion was limited and mainly focused on the South. The main expansion into the temperate zone took place during the Middle Ages. However, the more detailed fluctuations of viticulture, particularly in relation to climate oscillations are still difficult to follow. Pip remains are mainly associated with urban sites. This is a consequence of the actual consumption of grapes and may be evidence of a viticulture centered around urban areas. • Macroremains data to retrace the Holocene history of Vitis. • Unique database of 4449 site-phases for seeds and 1356 site-phases for wood remains. • First comprehensive picture of the spread of Vitis and viticulture in France. • Significant and consistent involvement of cities in viticultural activities. [ABSTRACT FROM AUTHOR]

Abundant mineral resources in the deep sea are prospected for mining for the global metal market. Seafloor massive sulphide (SMS) deposits along the Mid-Atlantic Ridge are one of the potential sources for these metals. The extraction of SMS deposits will expose adjacent marine ecosystems to suspended particle plumes charged with elevated concentrations of heavy metals and other potentially toxic compounds. Up to date there is no information about the impact of mining activities on deep-sea benthic ecosystems such as abundant deep-sea sponge grounds in the North Atlantic Ocean. Sponge grounds play a major role in benthic-pelagic coupling and represent an important habitat for a diversity of vertebrates, invertebrates and microorganisms. To simulate the effects of mining plumes on benthic life in the deep sea, we exposed Geodia barretti , a dominant sponge species in the North Atlantic Ocean, and an associated brittle star species from the genus Ophiura spp. to a field-relevant concentration of 30 mg L−1 suspended particles of crushed SMS deposits. Three weeks of exposure to suspended particles of crushed SMS resulted in a tenfold higher rate of tissue necrosis in sponges. All brittle stars in the experiment perished within ten days of exposure. SMS particles were evidently accumulated in the sponge's mesohyl and concentrations of iron and copper were 10 times elevated in SMS exposed individuals. Oxygen consumption and clearance rates were significantly retarded after the exposure to SMS particles, hampering the physiological performance of G. barretti. These adverse effects of crushed SMS deposits on G. barretti and its associated brittle star species potentially cascade in disruptions of benthic-pelagic coupling processes in the deep sea. More elaborate studies are advisable to identify threshold levels, management concepts and mitigation measures to minimize the impact of deep-sea mining plumes on benthic life. • Deep-sea mining particles have adverse effects on the sponge G. barretti. • Oxygen consumption and food uptake were affected by deep-sea mining particles. • Exposure to deep-sea mining particles resulted in higher sponge mortality. • Changes in microbial symbiont composition reflected decreased sponge health. • Sponge-associated brittle stars all perished after ten days of exposure. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental study of thermochemical conversion, phase transformations and chemical reactions during microwave pyrolysis of biomass (sawdust, straw, nutshells, rice husk, etc.). For the first time, the characteristics of the microwave co-pyrolysis of agricultural waste have been analyzed. The experiments aimed to register the yield of the main pyrolysis products (gas, char and bio-oil) by varying the following factors: type of biomass, particle size, type of absorber/catalyst, and composition of mixtures. The biomass particle size of 800 µm was optimal in terms of pyrolysis gas yield and quality. Pyrolysis of sawdust and straw had the maximum yield of combustible gas components in relation to CO 2. The volumetric concentrations of CO, CH 4 , and H 2 for these types of biomass were 20–70% higher than those for wheat bran, rice husk, and nut shell. Among the low-grade catalysts studied, carbon residue and charcoal were the most efficient in terms of maximizing combustible gas yield and reducing CO 2. These catalysts reduced the bio-oil yield by a factor of 1.2 and increased the yield of combustible gases by a factor of 1.3. Pyrolysis of mixtures showed significant synergy, both positive and negative. The minimum yield of gas with the worst quality was typical for the mixture "rice husk 50%, sawdust 50%". The maximum positive synergistic effects were recorded for the composition "rice husk 33%, sawdust 33%, and bran 33%". The combination of these components increased the yield of CO, CH 4 and H 2 by 5–24%, 8–53% and 2–45%, respectively, compared to other mixtures. Thus, microwave co-pyrolysis creates great scope for the conversion of those components that do not provide the required gas characteristics during individual pyrolysis. Pyrolysis of mixtures contributes to the utilization of a large amount of plant waste while maintaining the quality of the end products. [Display omitted] • Individual and co-pyrolysis of agricultural waste has been studied. • Particle size of 800 µm is the optimal for microwave pyrolysis of sawdust. • Carbon residue and charcoal catalysts maximize the quality of pyrolysis. • The highest efficiency is characteristic of microwave pyrolysis of sawdust. • CO, CH 4 and H 2 concentrations from sawdust and straw pyrolysis were maximum. [ABSTRACT FROM AUTHOR]

• Measures for reducing the carbon intensity of blast furnace ironmaking were introduced. • Influences of low-carbon ironmaking processes on fuel requirements are reviewed. • The introduction of alternative reductants cannot eliminate the need for metallurgical coke. • Sustainability of blast furnace ironmaking depends on improving the H/C replacement ratio. • Introduction of hydrogen promotes the solution loss and structural degradation of coke. The blast furnace technology is still the main ironmaking route with a current global share of 70%. Reduction of fossil carbon consumption and CO 2 emissions in blast furnace operations are essential for the decarbonization of steelmaking. Potential solutions such as introducing renewable carbon-based materials (torrefied biomass, charcoal), using hydrogen-enriched reducing gases (i.e., hydrogen gas, coke oven gas, reformed coke oven gas, green methane), oxygen enrichment with top gas recycling, and carbon capture and storage/utilization have been considered to decrease emissions. The enhanced sustainability of blast furnace operations depends primarily on improving the hydrogen-to-carbon replacement ratio. Hydrogen is an effective reducing agent, producing steam during the reduction of ferrous burden. The replacement of coke and PCI with hydrogen leads to reduced fuel rates and CO 2 emissions. Although implementing the innovative ironmaking solutions reduces coke and coal consumption, coke cannot be replaced entirely as it plays an irreplaceable role as a mechanical support network and the permeable layer for gas movement in the blast furnace. The injection of alternative reducing agents into the blast furnace alters the reaction environment by changing gas composition and temperature. Therefore, understanding the impacts of new reaction conditions on coke rate and quality requirements is important to both coal producers and steel manufacturers. This paper reviews the current understanding of how the introduction of alternative reducing agents into the blast furnace influences the gasification behavior, degradation mechanism, and consumption rate of coke. The review also identifies the knowledge gaps and future research opportunities in the field. [ABSTRACT FROM AUTHOR]

• Europium radionuclides were selected as model pollutant. • Real samples such as natural and seawater is used. • Novel nanocomposite material namely MPC is applied as adsorbent. • MPC possessed high specific surface area ∼ 2360 m2/g. Liquid radioactive waste (LRW) presents the most significant environmental hazard due to its high aggregate activity and rapid distribution in the environment. The paper presents the structure and adsorption characteristics features of a new nanocomposite material namely mesoporous carbon (MPC). Characterization studies depicts that the material obtained consisted of bundles of carbon nanotubes coated with a uniform layer of porous carbon shell. The study on the MPC porous structure disclosed that the resulting material possess a combination of micro and mesopores with a predominant size of 1–6 nm and a specific surface area of 2360 m2 g−1. Adsorption characteristics of the MPC were studied using the sorption of 152Eu radionuclide from natural and seawater. Activated charcoal, coconut charcoal, and a gel-type strong-acidic sulfonic cation exchanger were used as reference materials. The synthesized MPC was found to have the distribution coefficients (K d) of 152Eu over 3 × 106 cm3 g−1, which was 1–3 orders of magnitude higher than for the reference sorbents. The kinetics study of the 152Eu sorption on the MPC showed that the sorption equilibrium was attained in 5 min, three times less than the activated charcoal. High adsorption of MPC is associated with the colloidal of europium species on the developed surface of the carbon sorbent. Results conclude that the synthesized mesoporous carbon material makes a promising adsorbent for removing europium and other radionuclides, namely, cerium, lanthanum, zirconium, plutonium, and americium, from neutral solutions, where those radionuclides exist in either colloidal or pseudo colloidal form. [ABSTRACT FROM AUTHOR]

Excess phosphorous (P) in aquatic systems causes adverse environmental impacts including eutrophication. This study fabricated Fe(III) loaded chitosan-biochar composite fibers (FBC-N and FBC-C) from paper mill sludge biochar produced under N 2 (BC-N) and CO 2 (BC-C) conditions at 600 °C for adsorptive removal of phosphate from water. Investigations using SEM/EDX, XPS, Raman spectroscopy, and specific surface area measurement revealed the morphological and physico-chemical characteristics of the adsorbent. The Freundlich isotherm model well described the phosphate adsorption on BC-N, while the Redlich–Peterson model best fitted the data of three other adsorbents. The maximum adsorption capacities were 9.63, 8.56, 16.43, and 19.24 mg P g−1 for BC-N, BC-C, FBC-N, and FBC-C, respectively, indicating better adsorption by Fe(III) loaded chitosan-biochar composite fibers (FBCs) than pristine biochars. The pseudo-first-order kinetic model suitably explained the phosphate adsorption on BC-C and BC-N, while data of FBC-N and FBC-C followed the pseudo-second-order and Elovich model, respectively. Molecular level observations of the P K-edge XANES spectra confirmed that phosphate associated with iron (Fe) minerals (Fe-P) were the primary species in all the adsorbents. This study suggests that FBCs hold high potential as inexpensive and green adsorbents for remediating phosphate in contaminated water, and encourage resource recovery via bio-based management of hazardous waste. [Display omitted] • Chitosan-biochar composite fibers (FBC) were prepared from paper mill sludge. • FBCs showed higher phosphate removal efficiency compared to biochars. • Phosphate adsorption isotherm of FBCs fitted to Redlich–Peterson model. • Phosphate adsorption was governed mainly via chemisorption. • XANES spectra confirmed phosphate association with Fe minerals (Fe-P) on FBCs. [ABSTRACT FROM AUTHOR]

• Explore markets effects of biomass competition between steel and forest industries. • Soft-linking technical energy system model and economic forest sector model. • Regional competition disrupts biomass prices and allocation, and supply costs. • Steel industry must consider market effects of new bio-production investment. • Beneficial to co-locate bio-production plants with iron and steel industries. Significant use of forest biomass in the iron and steel industry (ISI) to mitigate fossil CO 2 emissions will affect the biomass availability for other users of the same resource. This paper explores the market effects of increased forest biomass competition when promoting the use of forest-based bio-products in the ISI, as well as the interactions between the ISI and the forest industries. We employ a soft-linking approach that combines a geographically explicit techno-economic energy system model and an economic partial equilibrium model of the forest industries and forestry sectors. This allows for iterative endogenous modelling of new equilibrium price developments for different biomass assortments, determining locational choice of bio-products and assessing optimal bio-products technology choices. The results indicate an upward pressure on biomass prices when bio-products are introduced in the ISI (up to 62%), which affects both forest industries and the ISI itself. Prudence is thus warranted not to render bio-production investments uneconomical ex-post by neglecting to include potential price effects in investment decisions. The estimated price effects can be mitigated by increased domestic biomass supply, adjustments of international trade or by revising relevant policies. Even though the results suggest that the price effects will affect the geographical preferences for individual bio-production plants, proximity to the ISI production facility and integration benefits are more important than the proximity to cheaper biomass feedstocks. Product gas production integrated at ISI sites emerges as particularly attractive, while charcoal production exhibits sensitivity to fluctuating markets, both regarding resulting cost for the ISI, and preferred production locations. [ABSTRACT FROM AUTHOR]

The manuscript presents an innovative and holistic approach to quantifying PAHs and BTEX emissions from the grilling process and indicates a novel driven–toxicity-based solution to recognize health effects related to BBQ emissions. The exposure scenario includes the type of grilling device, food type, and individual attitudes, but also a keen understanding of the broad health implications related to the gaseous/particulate PAHs emission, or age-related effects. The calculated incremental lifetime cancer risk (ILCR) associated with the exposure to PAH congeners and BTEX indicates an unacceptable level in the case of charcoal and briquette grilling with the highest values for professional cooks. The sum of 15 PAH concentrations in grilled foods was highest for meat grilling over charcoal briquettes – 382,020.39 ng/m3 and lowest for meat grilling on a gas grill – 1442.16 ng/m3. The emissions of BTEX from lump charcoal grilling were 130 times higher compared to the gaseous grill. In all considered scenarios lump-charcoal and charcoal briquettes grilling derive the ILCR above the 10−4, indicating negative effects of traditional grills on human health. The paper completes knowledge of wide-ranging health implications associated with BBQs, a topic that is almost completely unaddressed among the scientific community and policymakers. [Display omitted] • PAHs concentrations ratio for Gph/Pph varied from 0.49 to even 40.97. • Refining the methods of assessing PAH exposure from grilling processes is needed. • Including personal attitude toward BBQ into health risk scenario research is reasonable. • Briquette vs. gas emission products brought 3 orders of magnitude higher risk. • Full burning protects BBQ consumers against inhalation exposure. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage 5 (MIS 5) is well represented in palynological studies of North Atlantic marine cores but in only a handful of archeological sequences from the adjacent Iberian landmass. In this paper, we undertake a multi-proxy analysis of small mammal assemblages (insectivores, bats, and rodents) from a 6 m-thick succession, dated to MIS 5a-5b (Layers 7–22), situated in the southeastern edge of the Central Limestone massif of Estremadura at Gruta da Oliveira, near Torres Novas, Portugal. Application of quantitative (Habitat Weighting, Simpson's Diversity Index) and qualitative (Mutual Ecogeographic Range, Bioclimatic Model, Quantified Ecology) methods suggest that open woodland habitats were dominant through the time of accumulation with reconstructed mean annual temperatures (MAT) tracking the 18O curve from the NorthGRIP ice core, from the end of MIS 5c to the beginning of MIS 4. Our findings are consistent with the general trends derived from other Gruta da Oliveira proxies (wood charcoal, coprolite pollen, large mammal associations), limited evidence from other MIS 5 terrestrial sites in Iberia, and offshore marine palynological records. • Combined quantitative and qualitative methods to reconstruct MIS 5 at Gruta da Oliveira. • Small-mammal assemblage used as a proxy to apply these methods. • A landscape dominated by open woodlands habitats has been identified. • Findings are consistent with the trends reported from other Gruta da Oliveira proxies. • Results accord with data from marine core pollen and other MIS 5 Iberian sites. [ABSTRACT FROM AUTHOR]

Chromium (Cr) contamination in soil and water poses high toxicity risks to organisms and threatens food and water security worldwide. Biochar has emerged as a promising material for cleaning up Cr contamination owing to biochar's strong capacity to immobilize Cr. This paper synthesizes information on biochar modification for the efficient remediation of Cr contamination in soil and water, and critically reviews mechanisms of Cr adsorption on pristine and modified biochars. Biochar modification methods include physical activation via ball milling or ultraviolet irradiation, chemical activation via magnetization, alkali/acid treatment, nano-fabrication or loading of reductive agents, and biological activation via integrating biochars with microorganisms and their metabolites. Modified biochars often have multi-fold enhancement in Cr adsorption/reduction capacity than pristine biochars. Iron (Fe)-supported magnetic biochars have the most promising Cr removal abilities with high reusability of the biochars. Pre-pyrolysis modification with Fe could load Fe 3 O 4 micro-/nanoparticles on biochars, and increase the surface area and electrostatic attraction between chromate anions and biochar surfaces, and reduce Cr(VI) to Cr(III). Post-pyrolysis modification could enrich oxygen-containing functional groups such as C O and –OH on biochar surfaces and promote Cr reduction and adsorption. Future research directions for Cr mitigation using advanced biochar products are discussed in this review. [Display omitted] • Chromium (Cr) biogeochemistry and its remediation using pristine/modified biochars. • Negatively charged O-containing groups on biochar surfaces act as electron donors. • Iron-modified biochars exhibit high Cr removal ability and reusability. • Post-pyrolysis modification enriches O-containing functional groups on biochar. • Biochar-based nanocomposites are effective reductants and adsorbents for Cr(VI). [ABSTRACT FROM AUTHOR]

Many regions worldwide have experienced increasing wildfire activity in recent years and climate changes are predicted to result in more frequent and severe fires. Reconstruction of past fire activity offers paleoenvironmental context for modern and future burning. Pyrogenic polycyclic aromatic hydrocarbons (PAHs) have been increasingly used as a molecular biomarker for fire occurrence in the paleorecord and offer opportunity for nuanced reconstructions of fire characteristics. A suite of PAHs is produced during combustion, and the emission amount and assemblage is influenced by many variables including fuel type, fire temperature, and oxygen availability. Despite recent advances in understanding the controls and taphonomy of these biomass burning markers, the spatial scale of this proxy is unknown. In this paper, measurements of PAH fluxes preserved in a lake sediment archive from the Sierra Nevada, California were compared with a historical geographic information system (GIS) dataset of area burned up to 150 km distance from the lake to determine the spatial scales for which these biomarkers are reliable proxies of biomass burning. The PAH fluxes in the Swamp Lake sediments record a change in the relative anthropogenic and pyrogenic sourcing of PAHs. Anthropogenic pollution sources could explain why some PAHs (fluoranthene (Fl), pyrene (Py), benz[ a ]anthracene (BaA), retene (Ret), benzo[ a ]pyrene (BaP), dibenzo[ a , h ]anthracene (DA) and ideno[1,2,3- cd ]pyrene (IP)) did not correlate with area burned within 150 km. This indicates that individual PAHs may have different efficacies in recording area burned and be more susceptible to masking of fire signals by pollution sources. Despite these complications, we find that the PAHs naphthalene (Na), acenaphthene (Ace), fluorene (F), and anthracene (An) are reliable local proxies of area burned (within 40 km), whereas the PAHs phenanthrene (Phe), chrysene (Ch), benzo[ b ]fluoranthene (BbF), benzo[ k ]fluoranthene (BkF), and benzo[ g , h , i ]perylene (Bghi) are both reliable local (within 36 km) as well as more regional (as much as 75 km for phenanthrene (Phe), chrysene (Ch), and benzo[ g , h , i ]perylene (Bghi) or 150 km for benzo[ b ]fluoranthene (BbF) and benzo[ k ]fluoranthene (BkF)) area burned proxies. Comparisons of PAH fluxes with charcoal accumulation rates in the same sediments suggest that pyrogenic particulate transport modulates low to mid-molecular weight PAHs via adsorption. Overall, the results show that PAH records integrate a combination of spatial signals of area burned and measurement of individual PAHs may enable cross-scale paleofire reconstructions. • The spatial scales of PAHs as paleofire proxies are poorly understood. • We use fire data to determine PAHs' reliability in recording area burned. • The spatial fidelity of PAHs varies due to their variable chemical properties. • We provide the first source area constraints for PAHs as paleofire proxies. [ABSTRACT FROM AUTHOR]

The Changbaishan volcano, located in northeast China, produced a large amount of charcoal during the "Millennium Eruption" (c. 946 CE). In this paper, we report a high-resolution date for the eruption using multiple methods applied to the fossil charcoal and living trees, including wood anatomy, radiocarbon dating and tree-ring cross-dating. In addition, we develop a new floating annual-resolution tree-ring chronology spanning nearly 200 years that provides information about paleoclimate conditions. In our study, we identified 60 samples of charcoal as Larix olgensis based on anatomical characteristics and geographical location. Using these materials, we dated the eruption to the winter of 946 CE based on a combination of radiocarbon dating, traditional dendrochronological cross-dating and cambial cell growth status. This allowed us to develop an L. olgensis tree-ring width chronology covering 764–946 CE and 1715–2016 CE, with significant sensitivities to April–September temperature (p < 0.05). The tree-ring data have great potential to indicate extreme climate events; for example, we identify an extremely cold year in 903 CE. Such marker years can improve the reliability and accuracy of tree-ring data. Our study provides direct and precise tree-ring evidence for volcanic eruptions and anomalous climate years in the Middle Ages. [Display omitted] • Cambial activity enables us to date the Millennium Eruption to winter 946 CE. • The first chronology reaching the Middle Ages so far developed in northeastern China. • The chronology was assembled from volcanic charcoal and living larch. • This chronology is sensitive to temperature. [ABSTRACT FROM AUTHOR]

• Response surface methodology can effectively remove fluoride from SCC. • Determine the optimal treatment process in a conventional muffle furnace. • When the roasting temperature is 1499 °C, the treatment time is 3.33 h, and the average particle size is 10 mm, the fluorine removal rate reaches 88%. Spent carbon cathode (SCC) is a typical toxic and hazardous solid waste generated in aluminum electrolysis. The harmless treatment of SCC is extremely important for the aluminum electrolysis industry. Herein, the response surface methodology was used to investigate the best process for removing fluoride from the SCC of aluminum electrolysis using the roasting method. A Box–Behnken design (BBD) was used to investigate the effects of three independent variables, namely, particle size, roasting temperature, and treatment time, on the fluorine removal rate of the SCC. Seventeen groups of experiments were conducted according to these three factors. Statistical analysis system software and a second-order polynomial model were used to analyze the data and predict the response. The results showed that the particle size, roasting temperature, and treatment time significantly influenced fluoride removal in the SCC. Under optimum process conditions, the system predicted a fluoride removal rate of 87% for the SCC. Validation experiments were conducted on the fluoride removal rate of the SCC under optimum process conditions. The results showed that the actual value reached 88%. The X-ray diffraction analysis before and after calcination showed that a small amount of SiO 2 was converted into SiC through a carbon thermal reduction reaction after calcination. This paper provides a theoretical basis for the best process of roasting SCC to remove fluoride. It also has a certain guiding significance for other solid waste treatments. [ABSTRACT FROM AUTHOR]

• The partial black porcelain was prepared by simple firing method. • Wood charcoal can be used as carbon solid source for black porcelain production. • Graphite, amorphous graphitic carbon, and Si − O − C were detected in porcelain body. This paper observes the fabrication of partial black porcelain by carbon diffusion from wood charcoal as a solid carbon source, and the characterization of body at bottom area. The porcelain cup was created by conventional ceramic technique. For second firing step, the cup was set on the wood charcoal pieces contained in a closed refractory container and fired at 1250 °C for 1 h. The traces of carbon compounds at different positions on a cross-section sample were detected by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Graphitic carbon and Si − O − C were discovered. Furthermore, graphite peak was detected by X-ray diffraction (XRD). This work provides a confirmation of solid diffused carbon from wood charcoal into the porcelain body by scientific techniques. [ABSTRACT FROM AUTHOR]

As concerns about climate change and sustainability rise, biomass utilization has a potential to become one of the pillars of the future energy market. It is therefore critical to assure that solid biomass fuels are of the highest quality and do not contribute to avoidable air pollution. Our research has shown that petrographic analysis of solid biomass in reflected light can quickly and reliably provide information on fuel composition and contamination. As such, this technique has a potential to improve our understanding of raw fuel properties and, in some instances, even predict parameters of their combustion emissions. This paper provides guidelines for conducting microscopic analysis of wood pellets and charcoal-based fuels in reflected light. It presents two preliminary microscopic classifications of solid biomass components and emphasizes the need for training materials, exemplified by recently published photomicrograph atlases. Our research indicates that pairing reflected light microscopy with the currently used standard testing would enhance the quality assessment of solid biomass. To achieve this, the methodology must be promoted, tested for interlaboratory reproducibility, and finally standardized. • Solid biomass products contain a wide range of contaminations. • Reflected light microscopy is effective tool to study impurities in solid biomass. • Petrographic analysis can complement and enhance currently used quality testing. • Methodology requires further development, refining and ultimately standardization. [ABSTRACT FROM AUTHOR]

• A new 3-D bimetal organic framework (CeCu-MOF) was hydrothermally prepared. • The plant-charcoal obtained by hydrothermal method has the best electrochemical performance. • Different amounts of plant-charcoal was employed to form CeCu-MOF/C composites to improve the electrical conductivity. • For lithium-ion batteries, 10 wt% plant-charcoal performed best, while for supercapacitors, 20 wt% of plant-charcoal is best. [Display omitted] We prepared a novel three dimensional (3-D) 3d-4f MOF (named as CeCu-MOF; C 10 H 10 CeCu 2 N 4 O 12) which exhibits triclinic symmetry P-1 space group, and applied it to the study of electrode materials in organic system and aqueous solution system respectively. In order to overcome the shortcomings of poor electrical conductivity of MOF, we prepared several plant-charcoal materials with discarded grapefruit peel by different carbonization methods. The best electrochemical performance is selected for detailed study. In this paper, different amounts of plant-charcoal and MOF were used as electrode materials for supercapacitors and lithium-ion batteries, and their electrochemical properties were investigated. The results showed that the addition of plant-charcoal did help to improve the electrochemical performance compared with the single-phase MOF. [ABSTRACT FROM AUTHOR]

Archaeological evidence of Middle Palaeolithic sites in Europe dating to MIS 4 remains very scarce compared to those belonging to previous (MIS 5) and later (MIS 3) periods. Of the few documented, a very low number have provided anthracological data reflecting the local landscape and fuel gathering strategies during MIS 4 Neanderthal occupations. This factor especially limits our knowledge of local landscape dynamics and the climatic conditions where these human occupations occurred. In this paper we contribute to this context through charcoal data from De Nadale cave, a single-layered Mousterian site located in northeastern Italy (Berici Hills area) and dated to 70.2 + 1/− 0.9 ka BP. Anthracological data suggests the preferential use of spruce / larch (Picea - Larix) as firewood together with cryophilous pines (Pinus tp. sylvestris) and birch (Betula sp.) indicating prevailing harsh climatic conditions. Additional analysis focused on taphonomic features affecting charcoal point out to advance decay evidence prior to charring caused by fungi and insects. Although further data is needed, our results provide complementary information agreeing with the faunal spectrum, the small mammals assemblage and the nearby terrestrial pollen sequences • We analysed wood charcoal remains from a MIS 4 site in northeastern Italy. • The climatic conditions were cooler and more humid than currently. • Decay features recorded could indicate the presence of dead wood in the local area. • Post-depositional processes affecting the higher degraded charcoals are considered. [ABSTRACT FROM AUTHOR]

Our aim with this paper is to provide insight into the landscape dynamics of the Cantabrian region (northern Iberian Peninsula) from the Last Glacial Period to the present. We present a multiproxy approach performed in a sedimentary record from La Molina peat bog, located at 484 m a. s. l. in Puente Viesgo, Cantabria (Latitude: 43.26° N; Longitude: 3.97° W), that covers the last c. 17,550 years. Analyses were performed on the organic matter, pollen and sedimentary charcoals, which have been used to characterise the fire regime at a local level. The results revealed a steppe-like formation from the basis of the sequence to the Bølling-Allerød chronozone, when the spread of woody species is detected. The dry and cold conditions of the Younger Dryas caused the decrease of mesophilous taxa until the onset of the Holocene. From that point onwards, a mixed deciduous formation composed of Betula and deciduous Quercus was established in the region. Besides, a series of biomass pulses was detected during the early Holocene, probably linked to intervals of increased rainfall. Fire episodes detected at the 9.3 and the 8.2 ka events created forest openings and probably favoured the establishment of Corylus, most likely also helped by a climate shift. There was a lack of fire activity until the Neolithic, when the fire signal increased probably linked to grazing and agricultural practices and triggered deeper changes in the Cantabrian plant landscape structure. • There is no evidence of pine forests during the last 17.55 cal ka. • A steppe-like formation is revealed until the spread of Betula at 13.7 cal ka BP. • Fires triggered changes in landscape composition during the 9.3 and 8.2 ka events. • The spread of Corylus was likely helped by a climate shift and the fire activity. • Agriculture was accompanied by recurrent fire activity to create forest openings. [ABSTRACT FROM AUTHOR]

Disentangling fire and its controls over thousands of years ago is a major challenge in the study of paleofires. In this paper, we synthesize sedimentary charcoal and black carbon from the coastal plain of Laizhou Bay, China to improve our ability to reconstruct fire history in the past 5000 years, and to assess the controls of fire using principal component analysis and multiple regression approach. The results show that there were three distinct fire episodes at the intervals of 5300–5100 yr BP., 1190–1060 yr BP., and 300–0 yr BP., based on the Changyi (CY) profile. A large-scale fire episode was synchronous with a rapid climate variability that occurred 5300 yr BP., which had frequent drought and cold epoch. High fluxes of black carbon and charcoal were closely related to mass migration and the use of fire for land reclamation from 1190 to 1060 yr BP. Subsequently, anthropogenic biomass burning for cereal cultivation has reached a higher level over the past 300 years. However, between 4600 and 4000 yr BP. the shifts in the frequency of high-magnitude floods and climate aridity consequently resulted in the decline of fire-episode frequency and the abandonment of the late Neolithic settlements in the study region. Therefore, climate is still a prerequisite factor for fire occurrence on the southern coast of Laizhou Bay in the past 5000 years. A rapid climate variability was not only responsible for various fire patterns, but also could affect human settlements and the mode of production during middle-late Holocene. In the past 1000 years, human land use has been a more important control of fire. However, temperature has become one of the evidently identified controls of fire across the study area in recent decades. To synthesize the methods of Principal Component Analysis and Multiple Regression Analysis with multi-proxy evidence is necessary for us to better understand fire and its controls on coastal plain of Laizhou Bay at the region. • Charcoal and BC have recorded fire mid-Holocene at the Laizhou Bay of China. • Climate was still a prerequisite control of fire at the Laizhou Bay mid-Holocene. • In the past 1000 years, human land use has been an important control of fire. • Temperature has become one of the identified controls of fire across the study area. • Principal component analysis will contribute to disentangling fire and its controls. [ABSTRACT FROM AUTHOR]

• The LCA of steel production where coke is substituted with biocarbon is presented. • The total impact of green steel is about 1.6 kgCO2eq/kg of steel, • This impact is 31% lower than that of conventional steel. • 49% of the total impact of steel is represented by pig iron production. • Ferronickel production accounts for 27% of the total impact. According to the Financial Times the steel industry emissions accounted for 7–9% of total greenhouse gases emissions worldwide in 2019. The main contribution to those emissions is directly related to the use of fossil coke and coal as fuels and reducing agents. Four solutions can be adopted to address such issue: direct reduction with hydrogen or syngas, electric arc furnaces, carbon capture and storage and use of biofuels (for example the so called "biocarbon"). These solutions can be also integrated. We propose applying innovative methods to produce biocarbon by pelletizing charcoal with pyrolysis oils and reheating it at high temperatures, to obtain materials with sufficient hardness, reduced porosity and proper reactivity. Once upgraded biocarbon can comply with the requirements usually needed for metallurgical coke. We present in this paper the results of a technical and economic analysis plus an environmental analysis on the expected final use of biocarbon in the silicon and steel industry. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental studies on the silicon carbide powder synthesis from charcoal and silicon in plasma of DC low-voltage arc discharge in ambient air. The observed dependencies of the initial mixture composition, arc discharge duration and treatment cycles on the phase composition of synthesized products allow fabrication of the powdery product composed of two phases: graphite and cubic phase of silicon carbide. The powdery product contains crystals that correspond to the morphology of biomorphic wood-derived silicon carbide. The temperature range suitable for synthesis of powdery product with a removal of an excess of free carbon was established by the differential thermal analysis. The synthesis product consists mainly of carbon and silicon, and insignificant amount of impurities contained in the original charcoal. Oxygen is also present in the synthesis product in an amount up to 4.6 at. %, which may indicate the presence of an amorphous silicon oxide layer on the silicon carbide surface. The proposed method finally yielded the silicon carbide based powder with a lattice parameter a = 4.359 Å. • SiC powder was synthesized from charcoal and silicon in plasma of DC low-voltage arc discharge in ambient air. • The synthesized product composed of two phases: graphite and cubic phase of silicon carbide. • Oxygen is also present in the synthesis product in an amount up to 4.6 at. %. • The method finally yielded SiC powder with a lattice parameter a = 4.359 Å. [ABSTRACT FROM AUTHOR]

The Tarvagatai Nuruu National Park, situated in the northern Khangai Mountains in central Mongolia, is dominated by a forest-steppe ecosystem. An extreme continental and semi-arid climate is characteristic for forest-steppe ecosystems in Central Asia and their vegetation is very sensitive to climatic changes and human impacts by pastoralism and tree-logging. In the selected study area, nowadays human impact is exceptionally low, and it has potentially also been in the past. The focus of this paper was to reconstruct vegetation variability, climate dynamics, intensity of human impact and fire dynamics by applying a broad multi-proxy approach on a lacustrine sediment core from a small closed lake in the study area. The analyses include reconstructions of pollen, spores, non-pollen palynomorphs, and charcoal distribution as well as XRF-scanning. Overall, the radiocarbon-dated lacustrine sediment core reveals stable, long-term environmental conditions since the early Holocene (9570 cal yr BP). Palynological results indicate that vegetation varies on a comparably low level. We assume that nomadic pastoralism played a tangential role on the vegetation changes in the study area. Higher values of coprophilous fungi between 9570 and 8350 cal yr BP suggest the highest wildlife activity during the early Holocene. Hence, our multi-proxy data reveal a surprisingly stable vegetation composition and only slight climatic changes in north-central Mongolia for the entire Holocene. An initial moist and warm period from 9570 to 4180 cal yr BP was followed by a period of slightly drier and potentially cooler conditions from 4180 until 430 cal yr BP. The latest period from 430 cal yr BP to present was moist and warm. Fires were in general relatively rare except from a strong phase of fire activity between 3550 and 2960 cal yr BP. • A new multi-proxy record (pollen, NPPs, macro charcoal, XRF-data) from north-central Mongolia. • Detailed high-resolution Holocene palaeoecological record covering the last 9600 cal yr BP. • Reconstructed stable vegetation reflects limited human impact on the vegetation dynamics since the Early Holocene. • Values of coprophilous fungal spores during the early Holocene provide a baseline of wildlife activities. • Extensive fire episode from 3550 to 2960 cal yr BP. [ABSTRACT FROM AUTHOR]