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To promote the development of the green and low-carbon wood industry and explore the current status and trend of China's used-furniture recycling, this paper summarizes the research status of used-furniture recycling and interprets governmental strategies, such as the development of used-furniture recycling system, the way of handling used-furniture by manufacturers, and the attitudes of customers towards used-furniture, through extensive literature reviews and market research. From such three respects as government, furniture manufacturers, and consumers, the problems of national used-furniture recycling are analyzed, for example, imperfect system, high cost, and weak awareness. Therefore, to solve the above issues, it is necessary to construct national used-furniture recycling system and methods. The government should pay attention to the construction of recycling network, the supervision and support of entrepreneurial responsibilities, and the formulation of recycling standards. For furniture manufacturers, the improvement of the durability and recyclability of furniture and the development of new models and new technologies for furniture recycling and transportation are their primary assignment. And for consumers, the improvements of their concepts of consuming and the environmental protection are in focus. In sum, it aims to provide both suggestions for the amelioration of the measures and methods, and support for the understanding of the change, of used-furniture recycling in China.

This study was undertaken to determine the effect of wood dust on the respiratory system and oxidative stress in furniture workers and to determine whether any associations exist between respiratory parameters and oxidative stress.This cross-sectional study was performed on 45 furniture workers and 45 office workers as a reference group in Iran. The NIOSH method 0600 was used to determine the concentration of particulates. The prevalence of respiratory symptoms was estimated via the European Community Respiratory Health Survey (ECRHS) questionnaire. Oxidative stress biomarkers and respiratory parameters were also measured.The mean concentrations of respirable and non-respirable dust were found to be 1.51 mg/mThe present study results indicated that exposure to wood dust significantly increased respiratory disorders and confirmed the association between lung function parameters and oxidative stress.

Preservative treatments increase the durability of wood, and one of the alternative treatments involves the use of chromated copper arsenate (CCA). Due to the toxicity of CCA, the disposal of CCA-treated wood residues is problematic, and burning is considered to provide a solution. The ecotoxicological potential of ash can be high when these components are toxic and mutagenic. The aim of this study was to evaluate the toxicity and genotoxicity of bottom ash leachates originating from CCA-treated wood burning. Physical-chemical analysis of the leachates revealed that in treated wood ashes leachate (CCA-TWBAL), the contents of arsenic and chromium were 59.45 mg.L

Slurry fuels based on wood and coal processing and petroleum refinery waste are an environmentally friendly and economically feasible alternative to the conventional solid fuel-coal. As part of this experimental research, we compared a set of fuels (coal and coal-water slurries with and without petrochemicals) by normalizing and calculating the specific concentrations of pollutants from their combustion. The pollutant concentrations were normalized with respect to the mass of burnt fuel, the thermal energy released by combustion, specific mass emissions per unit time, specific maximum mass emissions, and specific mass emissions per 1 kg of fuel equivalent or 1 MJ of thermal energy. The key objective of this research was to develop a method for comparing composite fuels in terms of their relative environmental friendliness. As part of the research, coal combustion was notable for the peak emissions of gaseous pollutants irrespective of the fuel mass and combustion chamber temperature. When slurries were burnt, CO

Being one of the most common wood in furniture and decoration, Fraxinus mandshurica Rupr. (F. mandshurica) is a frequently used material for wood products. However, the resulting odor problem has not yet been solved so far. Thus, this study focused on exploring odor-active compounds and investigating the effect of environmental conditions on emission and odor attributes. F. mandshurica was studied via TD-GC-MS/O combined with microchamber. Totally, 15 kinds of key odor-active compounds were detected from F. mandshurica. The main odorous components were found to be aromatics, aldehydes and ketones, esters, alcohols and acids. Six kinds of attributes played a key role in the overall odor character of F. mandshurica. Fragrant was the predominant odor impressions, followed by vinegar and antiseptic solution. The proportion of the odor-active compounds concentration to total concentration decreased with an increase in the temperature and relative humidity, while the ratio of air exchange rate to the loading factor had little effect on this. The total concentration of F. mandshurica increased as the temperature and relative humidity increased, but these decreased as the ratio of air exchange rate to the loading factor increased, while the total odor intensity reduced with the rise in the ratio of air exchange rate to the loading factor. Time was found to be the most effective factor for eliminating emissions. Considering the environmental conditions in this study, 40 °C, 60% relative humidity and a 1.0 m

Developing strategies that counter the ongoing homogenization trends of home-garden agroforestry systems is required to maintain diversity and sustainability. This study aimed to map and characterize traditional enset-based home-garden agroforestry for managing sustainability in the Gurage socioecological landscape in Ethiopia. We generated plots and land use land cover (LULC) spatial data from orthophotomosaic and collected household survey data of the field. Five home-garden types were identified explicitly through integrating the home-garden composition, functional structure, and agroecological zones. Most home-garden types had similar horizontal functional structures in which perennial crops were planted close to homesteads, annual crops grew in outer fields, and woodlots were located at the end of the parcel. Diverse woody species, crop varieties, and plot sizes were identified in individual household parcels, and these varied across the home-garden types. Enset-based home-garden agroforestry production has been declining in the Ethiopian landscape because of socioeconomic changes and a lack of technological inputs. These challenges may compromise the community's food security with loss of the product diversity provided by the home-garden system. Thus, technological adoptions and scaling up of agroforestry practices according to the home-garden types are necessary for the continue provision of multiple contributions. This study demonstrated site-specific spatial characterization of the agroforestry systems by considering a holistic approach to reduce the local challenges and support the development of sustainable landscape management in an altering socioecological landscape.

The present study seeks to investigate the use of husbandry waste and sawdust in the construction of degradable pots as a suitable alternative to plastic pots. Six mixture ratios of cattle manure and sawdust (85:15, 80:20, 75:25, 70:30, 65:35, and 60:40) were used along with three types of natural binders (sheep's wool, cornstarch, and sheep's wool:cornstarch) in phase I of the project. Phase I was replicated in triplicate to identify the best composition for each binding agent. International standards dictate that evaluations of biological pots include investigations into thickness swelling, internal bonding, and water absorption. Mean comparison of the resultant factorial data using the Tukey and TOPSIS methods indicated that production of bio-pots with a mixture of 80% manure and 20% sawdust may provide the best results for all three pot types. Phase II of the project involved using field experiments and cultivation of tomato plants in direct comparison to a commercial sample pot. The optimal pots for each binding agent in phase I were used in the evaluation. Field tests showed pots produced with 80% manure and 20% sawdust using cornstarch for binding adhesion performed best in terms of degradability and physical and mechanical properties.

Oxalate oxidase (EC 1.2.3.4) is an oxalate-decomposing enzyme predominantly found in plants but also described in basidiomycete fungi. In this study, we investigated 23 fungi to determine their capability of oxalic acid degradation. After analyzing their secretomes for the products of the oxalic acid-degrading enzyme activity, three groups were distinguished among the fungi studied. The first group comprised nine fungi classified as oxalate oxidase producers, as their secretome pattern revealed an increase in the hydrogen peroxide concentration, no formic acid, and a reduction in the oxalic acid content. The second group of fungi comprised eight fungi described as oxalate decarboxylase producers characterized by an increase in the formic acid level associated with a decrease in the oxalate content in their secretomes. In the secretomes of the third group of six fungi, no increase in formic acid or hydrogen peroxide contents was observed but a decline in the oxalate level was found. The intracellular activity of OXO in the mycelia of Schizophyllum commune, Trametes hirsuta, Gloeophyllum trabeum, Abortiporus biennis, Cerrena unicolor, Ceriosporopsis mediosetigera, Trametes sanguinea, Ceriporiopsis subvermispora, and Laetiporus sulphureus was confirmed by a spectrophotometric assay.

Denitrifying woodchip bioreactors are a practical nitrogen (N) mitigation technology but evaluating the potential for bioreactor phosphorus (P) removal is highly relevant given that (1) agricultural runoff often contains N and P, (2) very low P concentrations cause eutrophication, and (3) there are few options for removing dissolved P once it is in runoff. A series of batch tests evaluated P removal by woodchips that naturally contained a range of metals known to sorb P and then three design and environmental factors (water matrix, particle size, initial dissolved reactive phosphorus (DRP) concentration). Woodchips with the highest aluminum and iron content provided the most dissolved P removal (13±2.5 mg DRP removed/kg woodchip). However, poplar woodchips, which had low metals content, provided the second highest removal (12±0.4 mg/kg) when they were tested with P-dosed river water which had a relatively complex water matrix. Chemical P sorption due to woodchip elements may be possible, but it is likely one of a variety of P removal mechanisms in real-world bioreactor settings. Scaling the results indicated bioreactors could remove 0.40 to 13 g DRP/ha. Woodchip bioreactor dissolved P removal will likely be small in magnitude, but any such contribution is an added-value benefit of this denitrifying technology. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-15835-w.

This study investigated experimentally pyrolysis of rubberwood sawdust (RWS), sewage sludge (SS), and their blends (25:75, 50:50, and 75:25 by weight) in an agitated bed pyrolysis reactor. The yields and characteristics of liquid product and biochar were determined for pyrolysis at 450, 500, and 550 °C and were affected both by temperature and feedstock type. The liquid and biochar yields were in the ranges 27.30-52.42 and 21.43-49.66 (wt%). Pyrolysis of RWS at 550 °C provided the highest liquid yield, while SS gave a high biochar yield. Co-pyrolysis of SS with RWS improved yield and quality of liquid and biochar products. The liquid product had 57.54-70.70 wt% of water and a low hydrocarbon content. The higher heating value (HHV) of water-free liquid product was 14.73-22.45 MJ/kg. The major compounds of liquid product included acetic acid, 2-propanone, 1-hydroxy, and phenols according to GC-MS. The biochar from RWS had a high carbon content (83.37 wt%) and a high HHV (33.57 MJ/kg), while SS biochar was mainly ash (67.62 wt%) with low carbon content. The SS biochar also had high contents of Si, Ca, Fe, K, and Mg as determined by XRF. Co-pyrolysis of SS with RWS improved the biochar by increasing its carbon content and reducing ash and inorganic elements. The surface of RWS biochar was more porous, while SS biochar had the larger specific surface according to SEM and BET. Based on these results, co-pyrolysis of 75:25 feedstock mix is recommended for further studies on applications of liquid product and biochar.

Lignin-decomposing ability of several bacteria and the degradation mechanism have been revealed in vitro. However, the abundance of such bacteria in decayed wood in nature remains unknown at genus and species levels. This study was aimed at identifying bacterial communities in the decayed wood coexisting with white-rot fungi, which play a potential role in lignin degradation, and predicting the functional profile of bacterial lignin degradation in wood via bacterial community analyses. The bacterial flora of forest soil and four decayed wood samples showed marked differences; particularly, in addition to Methylobacterium and Acidibrevibacterium, sphingomonads, which degrade the major skeleton of lignin in vitro, were more abundant in the decayed wood than in forest soil, suggesting that multiple bacteria were involved in lignin degradation. The bacterial community in the decayed wood was more influenced by wood type and lignin structure than the fungal species observed in the decayed wood.

There is an abundance of woody biomass in Japan. However, its economic feasibility is limited. There have been several discussions on whether generation of heat or electrical power is more suitable for woody biomass. In this study, we clarified the feasibility of generating heat and electricity from the viewpoint of biomass unit price and biomass productivity based on actual operation data for the first time. It was determined that heat production is feasible for a small-scale biomass energy use of 2,660 t/year or more. Electrical power generation is feasible only for a large-scale biomass energy use of 13,100 t/year or more, but it allows use of woody biomass with a higher unit price.

The development of building materials using new types of raw materials is currently on demand by society and the industry. It is intended to reduce production costs, improve properties and obtain ever-increasingly sustainable processes and products. In this respect, this work aimed to evaluate the effect of new types of reinforcement material on the physical-mechanical and thermal properties of cement-based panels. Cement-based panels reinforced with pine wood, coffee husk waste, rice husk and polyethylene terephthalate (PET) were evaluated. The panels were produced with 1.30 g.cm-3nominal density; 1:2.5 reinforcement material: cement ratio; 1:1.5 water:cement ratio; 0.25 cement hydration rate using Portland ARI V cement and 3% calcium chloride (CaCl2) as additive. The panels' physical, mechanical and thermal properties were evaluated before and after accelerated aging. PET bottle wastes showed great potential for use in cement-based panel production, obtaining the best physical and mechanical results, and showing superior performance to pine wood panels. Cement-based panels reinforced with coffee husk and rice husk waste obtained lower physical-mechanical performance, presenting usage limitations, however, with the lowest values of thermal conductivity.

In the paper, results of drying biofuels from sewage sludge using solar energy are presented. Drying rates of biofuels made from sewage sludge and coal slime (PBS), sewage sludge and meat and bone meal (PBM), and sewage sludge and sawdust (PBT) with 15-mm and 35-mm granule particle size were studied. Tests were performed in a solar greenhouse dryer equipped with a specially designed mixing system. Experiments were aimed at determining the drying time of biofuels under various weather conditions in the southwestern part of Poland. In summer, in order to determine the best conditions for drying, tests were performed using various parameters, i.e., layers of various thickness, such as 5, 10, and 20 cm, and various mixing intensity (no mixing, mixing 3 and 5 times/day). In spring and the fall, 10-cm thick layers combined with 5 times mixing of fuels per day were used. The performed tests demonstrated that it is beneficial to dry fuels in 10-cm thick layer. In spring and the fall, PBS and PBM biofuels laid out in layers with just such thickness showed moisture content reduced to less than 10% after 8 days, while the PBT biofuel reached the same level after 14 days. In summer, the same result may be obtained for all the biofuels after 4 days on average. The presented original method of solar drying of biofuels obtained from sewage sludge and other waste may be used in wastewater treatment plants which process sewage sludge into fuels without incurring any additional costs for supplying heat.

The thermal conversion of woody biomass is increasingly critical for the development of the energy processing technologies and fire safety engineering. The combustion characteristics, kinetics, and thermodynamics of pine wood were characterized through a thermogravimetric analyzer in the air atmosphere. There were two apparent peaks in the derivative TG curves for pine wood. The combustion process of pine wood was divided into two stages. Therein, the first stage occurring in the conversion degree range of 0-0.6 may be considered a one-step reaction. It was easier for pine wood to decompose under air than under nitrogen. Moreover, the first stage of pine wood combustion may be characterized by the diffusion model g(α) = [1 - (1 - α)1/3]2. The kinetic modeling showed a good agreement between the predicted and experimental conversion degree curves. In addition, the high comprehensive combustion index of pine wood at 10 K min-1 (6.73 × 10-7 %2 min-2 K-3) showed its great potential for bioenergy generation. Besides, both the value of ΔH and ΔS exhibited similar patterns with the activation energy value versus conversion degree, while the ΔG value almost remained at a positive constant with conversion degree. The average ΔH, ΔG, and ΔS value was nearly equal under different heating rates.

In this work, for the first time, Cordia trichotoma sawdust, a residue derived from noble wood processing, was applied as an alternative biosorbent for the removal of crystal violet by discontinuous and continuous biosorption processes. The optimum conditions for biosorption of crystal violet were 7.5 pH and a biosorbent dosage of 0.8 g L−1. The biosorption kinetics showed that the equilibrium was reached at 120 min, achieving a maximum biosorption capacity of 107 mg g−1 for initial dye concentration of 200 mg L−1. The Elovich model was the proper model for representing the biosorption kinetics. The isotherm assays showed that the rise of temperature causes an increase in the biosorption capacity of the crystal violet, with a maximum biosorption capacity of 129.77 mg g−1 at 328 K. The Langmuir model was the most proper model for describing the behavior. The sign of ΔG0 indicates that the process was spontaneous and favorable, whereas the ΔH0 indicates an endothermic process. The treatment of the colored simulated effluent composed by dyes and salts resulted in 80% of color removal. The application of biosorbent in the fixed-bed system achieved a breakthrough time of 505 min, resulting in 83.35% of color removal. The Thomas and Yoon-Nelson models were able to describe the fixed-bed biosorption behavior. This collection of experimental evidence shows that the Cordia trichotoma sawdust can be applied for the removal of crystal violet and a mixture of other dyes that contain them.

In this study, we estimated the technoeconomic availability of three types of dead trees, namely commercially fallen, normally fallen, and standing, in Mongolian subgroups. For dead trees of three major Mongolian tree species (Siberian larch, Scotch pine, and Asian white birch), lumber, firewood, and unused material as sources of energy were quantified and operational costs (marking, felling, skidding, transporting, loading/unloading, processing, and stumpage prices) were estimated. As a result, most Mongolian subgroups were profitable and suitable for the harvest of unused materials. Moreover, unused materials of dead trees can substitute nearly 5.45 million tons of coal, although it is not sufficient to meet the 0.6 years of coal demand across Mongolia. However, in some places, unused dead wood materials can completely substitute coal for decades. Therefore, although the heat utilization of woody biomass is not suitable for Mongolia as a whole, it is feasible in specific regions where forest resources are abundant, such as some Mongolian sub-provinces. Promoting the use of dead trees can reduce the risk of damage caused by wildfires and pests, which are serious problems in Mongolia, and keep the forests healthy. Furthermore, unused materials can generate new income opportunities, and the forest land can be well prepared by removing dead trees to promote planting for sustainable forest management. Finally, dead trees can be used as a resource until transition to sustainable forests with living trees.

The Oseberg ship is one of the most important archaeological testimonies of the Vikings. After excavation in 1904, the wooden gravegoods were conserved using alum salts. This resulted in extreme degradation of a number of the objects a hundred years later through acid depolymerisation of cellulose and lignin. The fragile condition of the artefacts requires a reconsolidation which has to be done avoiding water as solvent. We synthesized tert-butyldimethylsilyl (TBDMS) chitosan which is soluble in a 50:50 solution of ethyl acetate and toluene. Measurement of its molecular weight, to anticipate its penetration, provided a challenge as the density difference of the polymer and solvent was too small to provide adequate solute redistribution under a centrifugal field, so a two-stage process was implemented (i) determination of the weight-average molar mass of the aqueous soluble activated precursor, chitosan mesylate, Mw,mc using sedimentation equilibrium with the SEDFIT-MSTAR algorithm, and determination of the degree of polymerisation DP; (ii) measurement of the average degree of substitution DSTBDMS of the TBDMS group on each chitosan monosaccharide monomer unit using NMR, to augment the Mw,mc value to give the molar mass of the TBDMS-chitosan. For the preparation, we find Mw = 9.8 kg·mol−1, which is within the acceptable limit for penetration and consolidation of degraded wood. Future work will test this on archaeological wood from different sources.

Camphor wood is welcomed by museums due to its insect-repelling effect but the smell indicates a potential risk to the collections. In order to judge the suitability of camphor wood as a museum storage material, typical camphor wood (Cinnamomum camphora) samples aged for different years were evaluated by conducting the Oddy test. Gas chromatography–mass spectrometry (GC-MS), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and time of flight–secondary ion mass spectrometry (ToF-SIMS) were applied to identifying the volatile organic compounds (VOCs) emitted by the materials and the corrosion products, respectively. The results showed that the camphor wood samples led to visible corrosion on copper and lead coupons. GC-MS indicated that the major VOCs emitted were terpenes and their derivatives, while XRD, EDS, and ToF-SIMS provided various clues to the corrosion mechanisms. Pb10(CO3)6(OH)6O and CuO were regarded as the major corrosion products of lead and copper coupons, respectively. The study provides the museum curators and the conservators with abundant information to reassess the application of camphor wood to museums as well as a different way to understand the mechanism of metallic corrosion caused by camphor wood.

To evaluate a strain of Fusarium verticillioides ITV03 isolated from wood residues in the Veracruz region of Mexico. Endoglucanase and β-glucosidase production by submerged fermentation was optimized using a Box–Behnken design, where the independent variables were urea, ammonium sulfate and yeast extract. After optimization, an endoglucanase activity of 0.27 U/mL was achieved; subsequently, three carbon sources were evaluated (carboxymethyl cellulose, sweet sorghum bagasse cellulose and delignified sweet sorghum bagasse (DSSB). The results showed that DSSB yielded the greatest endoglucanase (0.28 U/mL) and β-glucosidase (0.12 U/mL) activities. Both enzymatic activities were characterized for the effect of pH, temperature and thermostability. The optimal parameters of β-glucosidase and endoglucanase activity were pH 5 and 4 respectively, the optimum temperature 60 °C. These enzymes were stable at 50 °C for 150.68 h and 8.54 h, with an activation energy (Ea(day)) of 265.55 kJ/mol and 44.40 kJ/mol respectively, for β-glucosidase and endoglucanase. The present work shows that a native strain like F. verticillioides ITV03 using DSSB supplemented with nitrogen has a great potential as a producer of cellulase for lignocellulosic residue hydrolysis.

Organosolv pretreatment with two ethanol concentrations (25% and 50%, v/v) was performed to improve enzymatic saccharification of poplar sawdust. It was found that lower ethanol concentration (25%, v/v) pretreatment resulted in a higher enzymatic digestibility of poplar (38.1%) due to its higher xylan removal and similar lignin removal ratios, compared to that pretreated with 50% (v/v) ethanol pretreatment (27.5%). However, the residual lignin still exhibited a strong inhibition on enzymatic hydrolysis of organosolv-pretreated poplar (OP). Bio-surfactant preparations including tea saponin (TS), TS crude extract, and tea seed waste were applied in enzymatic hydrolysis of OP, due to their potential ability of reducing enzyme non-productive binding on lignin. Their optimal loadings in enzymatic hydrolysis of OP were optimized, which indicated that adding 0.075 g/g glucan of TS improved the 72-h glucose yield of OP by 48.3%. Moreover, adding TS crude extract and tea seed waste exhibited the better performance than TS for improving enzymatic hydrolysis of OP. It was verified that the presence of protein in TS crude extract and tea seed waste accounted for the higher improvement. More importantly, the directly application of tea seed waste in enzymatic hydrolysis could achieve the similar improvement on enzymatic hydrolysis of OP, where chemosynthetic surfactant (PEG6000) was added. The residual enzyme activities in supernatant of enzymatic hydrolysis were also determined to reveal the changes on enzyme adsorption after adding surfactants. Generally, tea seed waste could be directly applied as an alternative to chemosynthetic surfactants to promote enzymatic hydrolysis of lignocelluloses.

Heavy metals induce stress in plants, thereby affecting growth, crop quality, and food security. Most studies addressing the mitigation of these effects by soil amendment have focused on metals in soils and plant uptake, with there still being a great deal of uncertainty about how amendment application in polluted soils can modify plant stress response and, consequently, yield and food safety. Thus, the aim of this study was to evaluate the effect of biosolid compost amendment on stress response, growth, and lead accumulation in Glycine max, when applied to lead polluted agricultural soils. Soybean was grown in lead polluted soils with 0%, 5%, or 10% (w/w) biosolid compost amendment under controlled conditions in a greenhouse, and the stress response indicators chlorophylls, proteins, sugars, malondialdehyde, glutathione S-transferase activity, carotenes, and the ferric reducingantioxidant power were investigated. In addition, the biomass and lead accumulation in different organs were determined and evaluated with respect to the plant stress. Our results revealed that the addition of 10% biosolid compost improved the grain biomass and appeared to reduce the amount of defective grains, which was related to higher Pb concentrations. Furthermore, 10% compost treatment reduced the stress in plants, leading to a better performance of the photosynthetic system, and with the antioxidant response being positively correlated to Pb accumulation. Lead uptake in plants was decreased by between 35 and 57%after this treatment in comparisonwith unamended soils. These results indicate that biosolid compost amendment may be an effective way to alleviate Pb uptake and metal stress in soybeans. Fil: Vergara Cid, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Ferreyroa, Gisele Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Pignata, María L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Rodriguez, Judith Hebelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

MicroRNAs (miRNAs) play crucial roles in all aspects of plant growth and development, but the genetic interactions of miRNAs and their target genes in woody plants are largely unknown. Here, we integrated association genetics and expression profiling to decipher the allelic variations and interactions of the Pto-MIR319 family of miRNAs and 12 putative Pto-miR319 target genes related to wood formation in 435 unrelated individuals of Populus tomentosa Carriere (Chinese white poplar). Expression pattern analysis showed that among all pairings between expressions of pre-miRNA of Pto-MIR319 members and targets, 70.0% showed negative correlation of expression levels (r = – 0.944 to 0.674, P

The kinetics, thermodynamics, and volatile products of camphorwood pyrolysis were investigated via thermogravimetry coupled with Fourier transform infrared (FTIR) spectroscopy at multiple heating rates. The kinetic triplets and thermodynamic parameters were estimated via model free combined with the model-fitting approach. The results showed that the pyrolysis of camphorwood in the conversion rate range from 0 to 0.85 might be considered as one-step process. The mean value of the activation energy and pre-exponential factor was 192.63 kJ/mol and 2.38 × 1013 s−1, respectively. The pyrolysis process (0 ≤ α ≤ 0.85) can be described by the three-dimensional diffusion model g(α) = [(1−α)−1/3 – 1]2. Furthermore, the predicted curves of the conversion rate α showed good agreement with the experimental curves. The values of ΔH, ΔG, and ΔS varied little with α and remained positive. In addition, the major gas products released from the camphorwood waste pyrolysis were H2O, methane, CO2, CO, C=O, O–H, C–O–C, and NH3, whose concentration in the order from highest to lowest was C=O > CO2 > O–H > H2O > methane > NH3 > C–O–C > CO. The main conclusions in the present study can provide guidance for the design and optimization of industrial reactor and selection of target biofuels or chemical raw materials.

Biochar was prepared by mixing sewage sludge with sawdust via a co-pyrolysis with different mixture ratios and temperatures. The results showed that the sawdust addition resulted in a lower yield of biochar with higher C content. The total concentrations of Pb and Cd in biochar were reduced. Besides, pyrolysis can transform the potentially toxic Pb and Cd to stable fractions. However the sawdust addition had slight influence on the chemical forms of Pb and Cd in the biochar. The biochar with 50% sawdust at 600°C exhibited a remarkable reduction of the leachable metal concentrations. The possible transformation mechanisms of Pb and Cd were inferred as the formation of aluminum and silicon-containing minerals. These results provide insights into the influence of sawdust addition on the characteristics of biochar and the possible Pb and Cd immobilization mechanisms during co-pyrolysis process.

This study evaluated the effect of wood extracts from Tectona grandis, Dalbergia sissoo, Cedrus deodara, and Pinus roxburghii combined with linseed oil as protectants of two non-durable wood species against the termite, Heterotermes indicola. Heartwood blocks (19 × 19 × 19 mm) and wood shavings were extracted using an ethanol/toluene (2:1) solvent system. Results of choice and no-choice tests with solvent-extracted and non-extracted heartwood blocks showed greater wood mass loss from termite feeding on solvent-extracted blocks compared with non-extracted blocks for all wood species. Significantly higher termite mortality was observed after termite exposure to non-extracted blocks compared with extracted blocks for all durable species. Sapwood blocks of two non-durable wood species (southern pine and cottonwood) were vacuum/pressure impregnated separately with each of the four types of extract at a concentration of 7.5 mg ml−1, linseed oil (20%) and a mixture of oil (20%) and extracts (4.25 mg ml−1) for the laboratory and field tests. Results showed that extract-oil mixture imparted significantly higher termite resistance compared with linseed or extracts alone under laboratory conditions. This apparent synergistic effect was clearly noted when linseed oil was combined with extracts from T. grandis or D. sissoo followed by an extract-oil mixture using C. deodara. These extract oil mixtures showed significantly less weight loss for the treated non-durable wood species and higher termite mortality (83–100%) compared with the control treatments and other extract-linseed oil mixtures tested. Treatment of both non-durable wood species with T. grandis + oil and D. sissoo + oil prevented termite damage compared with other treatments when blocks and stakes were exposed in the field for a period of 2 years. Results of the current study indicated that a mixture of a particular heartwood extract with linseed oil has potential to be used as environmentally friendly wood protectants.

When biochar (BC) is applied to soil, one process that can alter its properties and contaminant sorption is the leaching of minerals and dissolved organic carbon (DOC). This study investigated changes in properties of three BCs (cattle manure, grain husk, and wood chips), due to leaching, and the subsequent impact on sorption of trichloroethylene (TCE) and tetrachloroethylene (PCE). The manure-derived BC released 27.4 mg g−1 DOC, which is over ten times more than that measured for the two plant-based BCs (2.5 and 1.5 mg g−1 DOC for grain husk and wood chips, respectively). In all leachates, potassium is the dominant cation, whereas chloride, sulfate, and phosphate are the main anions. In total, the manure-derived biochar released the highest sum of total ions (73.1 mg g−1), followed by BC produced from grain husk (15.5 mg g−1) and wood chips (1.2 mg g−1). Leaching increased external surface area, mesopore volume, and hydrophobicity of the manure-derived BC and decreased its polarity. This enhanced sorption via partitioning. In plant-based BCs, micropore volume and size distribution were altered, most likely through the un-blocking of pores, causing increased sorption via pore-filling for both TCE and PCE. The results indicate that, depending on feedstock material, BC leaching can alter the environmental fate of organic compounds.

PURPOSE The aim of this study is to investigate the effect of wood dust on nasal mucociliary clearance time in wood industry workers. Moreover, the correlation between duration of exposure to wood dust and nasal mucociliary clearance time will be evaluated. METHODS A total of 50 male subjects were included in the study. All of the subjects were non-smokers. Nasal mucociliary clearance time of 25 wood industry workers was measured with saccharine method and compared with the results of 25 age-matched control group. Also, the correlation between nasal mucociliary clearance time and duration of exposure to wood dust in woodworkers was evaluated. RESULTS The mean mucociliary clearance time in control group and wood industry workers was 12.28 ± 1.98 and 16.72 ± 2.71, respectively. The mean mucociliary clearance time in wood industry workers was significantly longer than control group (p

Background Hangadi watershed is endowed with the only virgin forest in Odo shakisso harbouring high biodiversity, but it has been suffered from anthropogenic activities. This study was conducted to investigate composition and community diversity of woody species in restoration for posterity. Satellite images of 1988, 2008, and 2018 were used to classify and analyse trends of deforestation. For both woody species and topsoil (0–30 cm), 20 m × 20 m, 100 plots laid at every 300 m along line transects, 1 km apart from each other. In each sample plot, woody species ≥ 3 m were counted, Shannon–wiener diversity index, cluster analysis and ordination were computed. Results Agroforestry is found to be the dominant land use/land cover class followed by forest and cultivated land. A total of 61 woody species belonging to 34 families; 8.2% of the species were endemic to Ethiopia. The highest number of species was recorded from families Euphorbiaceae and Rubiaceae (5 species, 8.2%), Rutaceae, Celastraceae, and Oleaceae (3 species, 5.08%) followed by Flacourtiaceae, Meliaceae, Araliaceaae, Myrsinaceae, Moraceae, Boraginaceae, Asteraceae, Spontaceae, Lauraceae and Sapindaceae (2 species each). Four woody plant communities were identified using free statistical software R version 3.1.1. The canonical correspondence analysis result showed that EC, pH, OM, altitude, C:N, CEC, sand, silt, AvP, and TN significantly affected species distribution in the watershed. Conclusion Local people involved in cutting mature woody species for timber production, making farm implements and, cultivated land expansion. Protection of woody species diversity of forest and coffee systems with low biodiversity value conservation concepts are recommended to be executed jointly by local people and stakeholders.

Under the effect of disturbances, like unbalanced stem, but also during normal development, poplar trees can develop a specific secondary xylem, called "tension wood" (TW), which is easily identifiable by the presence of a gelatinous layer in the secondary cell walls (SCW) of the xylem fibers. Since TW formation was mainly performed on 2-year-old poplar models, an in vitro poplar that produces gelatinous fibers (G-fibers) while offering the same experimental advantages as herbaceous plants has been developed. Using specific cell wall staining techniques, wood structural features and lignin/cellulose distribution were both detailed in cross-sections obtained from the curved stem part of in vitro poplars. A supposed delay in the SCW lignification process in the G-fibers, along with the presence of a G-layer, could be observed in the juvenile plants. Moreover, in this G-layer, the immunolabeling of various polymers carried out in the SCW of TW has allowed detecting crystalline cellulose, arabinogalactans proteins, and rhamnogalacturonans I; however, homogalacturonans, xylans, and xyloglucans could not be found. Interestingly, extensins were detected in this typical adaptative or stress-induced structure. These observations were corroborated by a quantitation of the immunorecognized polymer distribution using gold particle labeling. In conclusion, the in vitro poplar model seems highly convenient for TW studies focusing on the implementation of wall polymers that provide the cell wall with greater plasticity in adapting to the environment.

Combustion (pyrolysis with oxygen) and pyrolysis without oxygen are two potential methods to convert wood into biofuels or biochemicals. To evaluate which is preponderant to convert wood into biofuels or biochemicals and provide guidance for optimization of product yield, the pyrolysis characteristics and kinetics of typical hardwood (black walnut) are comparatively investigated in nitrogen and air employing thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). Two model-free methods including Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) method are applied to obtain the kinetic parameters, and a model-fitting method called Coats–Redfern (CR) method is employed to estimate the reaction mechanism. The black walnut pyrolysis in nitrogen may be divided into two stages with the threshold of conversion rate α = 0.4, but that in air may be separated into three stages with the thresholds of α = 0.25 and 0.7. The reaction mechanism for pyrolysis in nitrogen may be assumed random nucleation and its subsequent growth, but that in air may be assumed random nucleation and its subsequent growth followed by chemical reaction. The average activation energy and natural logarithm of pre-exponential factor for the whole pyrolysis process in nitrogen and air are 211.59 and 187.73 kJ/mol and 32.33 and 28.36 min−1, respectively.

In order to investigate the influence of different lignin sources on humic substance formation during composting, this study selected two lignin sources, including wood sawdust and maize straw, to be co-composted with pig manure. Humic substances (HS) were characterized based on their fluorescence characteristics and complexing behaviors with heavy metals. The results showed that lignin sources, especially wood sawdust, were more conducive in promoting the formation of humic acids (HAs) than inorganic matter. The fluorescence excitation–emission matrix spectra also proved the positive effects of lignin on the formation of HAs during the humification process. The binding capacities of HAs isolated from mature composts for Cu and Cd followed the order of WS-90 > MS-90 > I-90, indicating that organic bulking agents are superior at increasing the complexing capacity of HAs. This finding suggests that the co-composting of pig manure with ligneous bulking agents is more advantageous at reducing the environmental risk of heavy metals.

To report a simple and novel method for intra-operative planning of fibula free flap reconstruction by means of a balsa wood (BW) model. Retrospective chart review. Between 2010 and 2015, 29 patients underwent mandibular reconstruction by a BW osteotomy design in which a single BW beam (US$4) is cut into segments to match the plate. The segments are then assembled together in a three-dimensional (3D) fashion to conform to the contour of the defect and the angles of attachment. Osteotomies are then performed according to the BW segment lengths and angles. Outcomes were retrospectively analyzed for number of procedures, operative times, and complications between the balsa wood method and more standard techniques, e.g., conventional 3D models. The length of the average mandibular defect was 9.62 cm (4–19), and the mean number of fibula segments was 2.03 ± 0.92 (range 1–4). Only one case (3.4%) necessitated revision surgery. Three patients (10.3%) had minor complications. Comparison of the results of the 13 patients reconstructed solely by BW to the 16 reconstructed by both BW and a 3D-printed model revealed that the use of BW alone did not significantly alter the average number of segments [2.31 (BW) vs 1.69 (combined); P = 0.07] or ischemia time (173 min vs 171 min, respectively, P = 0.938). The use of balsa wood as a model for intra-operative planning of fibula free flap osteotomies is an effective, inexpensive, and safe technique.

This study intended to help illustrate the Mn accumulation ability of Camellia oleifera and provide it as a novel species for possible use in Mn-contaminated sites. Field surveys have been carried out on Mn accumulation in C. oleifera growing near Mn mining area in Hezhou. Pot growth experiments in soil and sand culture were conducted to investigate Mn tolerance, accumulation, and translocation patterns in C. oleifera. C. oleifera grew well and showed no symptoms of Mn toxicity at a Mn treatment level below 1026 mg kg−1 in soil culture and 15.0 mmol L−1 in sand culture. Mn concentrations in leaves and stems reached a maximum of 9612.8 ± 83.5 and 6134.8 ± 94.0 mg kg−1, respectively, in soil culture and 28,465.8 ± 1276.7 and 15,398.4 ± 1148.6 mg kg−1, respectively, in sand culture. Meanwhile, most of the Mn taken from the substrates was transported to the aboveground tissues in soil and sand culture, e.g., over 92.07% of the total Mn taken up by C. oleifera was translocated to shoots in the 10.0 mmol L−1 treatment. Our findings confirmed that C. oleifera exhibited extraordinary Mn accumulation and toleration abilities, and C. oleifera was a suitable species for phytoremediation of Mn-contaminated sites in Guangxi Province.

Advancements in the design and technology of constructed wetlands for efficient removal of wastewater contaminants are ever in progress to develop situation-based economical systems. Here, we entrenched two horizontal sub-surface flow constructed wetlands (HSFCW) with either chemical, viz. limestone (HSFCW-LS) or organic, viz. sawdust (HSFCW-SD) substrates, and compared them with biological method, viz. growing of water spinach in floating-bed-constructed wetland (FBCW-WS) to enhance the performance of CWs. Same sewage wastewater was used as influent in each fortified CW replicated thrice. Sewage was replaced weekly, for a total of 12 weeks of experimentation. Sampling of raw sewage from influent was undertaken at the inlet in the beginning, and that of treated effluent from the outlet after a week of treatments. Quality of raw sewage used weekly during experimentation remained almost uniform and near to the wastewater standards. Cumulative data of treated wastewater depicted that the FBCW-WS achieved the highest performance in the removal of total nitrogen (TN), $$ {\mathrm{NH}}_4^{+} $$ –N, and total phosphorus (TP) with average removal efficiencies of 75.9, 90.5, and 94.3%, respectively. Whereas, HSFCW-SD performed better for $$ {\mathrm{NO}}_3^{-} $$ –N, FC, and TSS with corresponding removal efficiency of 77.5, 64.3, and 74.2% while HSFCW-LS showed average performance. This study concludes that performance of biological method of macrophyte cultivation (FBCW-WS) is significantly superior to chemical and organic substrates, so it could be more effective, economical, and sustainable approach for sewage treatment.

Poplar wood hemicellulose prehydrolysate was used for microbial oil production using an oleaginous microorganism Cryptococcus curvatus. Initially, the effect of substrate concentration and nitrogen content was investigated on synthetic media. Then poplar wood prehydrolysate without detoxification was used as substrate in the fermentation. The result showed that this strain is capable of consuming both hexose and pentose sugars, a challenge in fermentation of hemicellulosic streams. It was able to accumulate 36.98% of lipid and the fermentation resulted in 13.78 g/L of biomass and 5.13 g/L of lipid under optimum conditions after 164 h of fermentation. The lipid product obtained was characterized in terms of their fatty acid profiles. Overall, this study shows that it is possible to produce microbial oil from a sustainable renewable feedstock like poplar wood hemicellulose prehydrolysate. This robust strain used has the ability to grow on industrially produced hemicellulose which can help in the development of an integrated biorefinery, where all the three components of lignocellulosic biomass are utilized.

To investigate the spatial and historical distributions, and source contributions of polycyclic aromatic hydrocarbon (PAHs) from the middle reach of Huai River, 15 surface sediments and two sediment cores were analyzed. The Σ16 PAHs levels in surface sediments varied from 533.15 to 1422.83 ng/g dw, and from 413.27 to 43951.56 ng/g dw in individual sediment layer of sediment cores. The temporal trends of PAHs in sediment cores are the good indicators of the anthropogenic emissions over the last 60 years. The stable carbon isotope ratios of PAHs indicate the primary PAHs sources were the combustion of wood and coal during 1950s–1970s, and automobile exhausts and the coal combustion emissions in recent decades.

This study presents the characteristics of black carbon aerosol (BC) over a high-altitude site, Mahabaleshwar during the monsoon season. The mass concentration of BC exhibits a morning peak and a daytime build-up with a mean mass concentration of 303 ± 142 ng m−3. The simultaneous measurements of aerosol particle number concentration (PNC), cloud condensation nuclei concentration (CCN), and non-refractory particulate matter less than 1 μm size (NR-PM1) were also made by using a Wide-Range Aerosol Spectrometer (WRAS), CCN counter and Aerosol Chemical Speciation Monitor (ACSM) respectively. The source apportionment using wavelength-dependent light absorption model reveals the dominance by wood burning sources during morning hours and traffic sources during remaining hours of the day. The diurnal variation of PNC follows the variability of BC mass concentration. However, CCN concentrations were high during the morning hours coinciding with the increased fractional contribution of organics. The k-means clustering coupled with fuzzy algorithm highlights the effect of different sources on aerosol size distribution. On the basis of size distribution curve, the 3 clusters were attributed to wood burning (mean diameter range: 50–100 nm), traffic (30–50 nm), and background aerosols (65–95 nm). The combined analysis of k-means clustering, fractional contribution of organics, and kappa variation suggests that higher CCN concentration during morning is mainly attributed to probable emission of the water-soluble organic/inorganic compounds from wood burning.

It was the aim of this work to evaluate the adsorptive performance of the biochar obtained from the gasification of wood residues onto a solution of Indosol Black NF1200 dye. The study was performed by means of factorial design 22, having as control variables: pH and adsorbent’s granulometry. Batch tests were carried out at 200 rpm for 3 h (T = 28 °C). As output variable, the percentage removal of dye was determined. The best operating conditions were pH = 2 and 100 mesh granulometry. Also, adsorbent dosage studies were carried out, as well as equilibrium and adsorption kinetics. Both kinetics and equilibrium of adsorption tests were proceeded in basic and acid medium. For a basic pH value (pH = 12), it was concluded the equilibrium was reached in about 3 h of experiment, the experimental qmax value was near 12 mg g−1, and the equilibrium data fitted the Langmuir model. On the other hand, for tests with pH = 2, the equilibrium was reached after 5 min of experiment, the experimental qmax value was over 185 mg g−1, and the equilibrium data fitted both the Langmuir and Freundlich models. Thus, the biochar produced via gasification of wood wastes appears to be a promising adsorbent for the removal of azo dyes from textile wastewater, especially when working at lower pH values. Also, for a 10-kg/h consumption of wood residue, approximately 10 kW of energy is generated and 1 kg of biochar is produced, which represents another advantage from the environmentally friendly point of view.

Environmental impacts of mining activities are well known, particularly on-site degradation, but long term effects are less known. Mercury content from vegetation samples from a mine dump and surrounding forests was quantified for understanding the fate of this element in the local the environment. The study area, Tlalpujahua, Michoacán, México, has a mining history going back more than 400 years. Including gold and silver extraction by means of mercury amalgamation for 352 years (1554-1906). Mercury was present in all sampled materials. The highest values correspond to wood samples from the mine dump (13.84 ± 3.88 ppm), while wood samples from adjacent forests had 4.3 ± 2.4 ppm, almost twice as much as coniferous needles, shrub leaves and corn seeds (2.2 ± 0.34 ppm). The highest concentration was found for J. deppeana wood (16.05 ± 2.3 ppm). The capacity of accumulating mercury by Juniperus trees when growing on the mine dumps suggests that this species has a potential to be used for biosequestration purposes.

Background Exposure to particulate matter (PM) from wood combustion represents a global health risk, encompassing diverse exposure sources; indoor exposures due to cooking in developing countries, ambient PM exposures from residential wood combustion in developed countries, and the predicted increasing number of wildfires due to global warming. Although physicochemical properties of the PM, as well as the exposure levels vary considerably between these sources, controlled human exposure studies may provide valuable insight to the harmful effects of wood smoke (WS) exposures in general. However, no previous review has focused specifically on controlled human exposure studies to WS. Results The 22 publications identified, resulting from 12 controlled human studies, applied a range of combustion conditions, exposure levels and durations, and exercise components in their WS exposure. A range of airway, cardiovascular and systemic endpoints were assessed, including lung function and heart rate measures, inflammation and oxidative stress. However, the possibility for drawing general conclusions was precluded by the large variation in study design, resulting in differences in physicochemical properties of WS, effective dose, as well as included endpoints and time-points for analysis. Overall, there was most consistency in reported effects for airways, while oxidative stress, systemic inflammation and cardiovascular physiology did not show any clear patterns. Conclusion Based on the reviewed controlled human exposure studies, conclusions regarding effects of acute WS exposure on human health are premature. Thus, more carefully conducted human studies are needed. Future studies should pay particular attention to the applied WS exposure, to assure that both exposure levels and PM properties reflect the research question.

In studying indoor air quality, the concentration of volatile organic compounds (VOCs) emitted from wood-based panels and products is considered a main influencing factor. VOCs with low concentrations, even below the detection limit, can also have negative effects. Herein, VOCs emitted from particleboards and laminated boards were collected and analysed by GC-MS, and key odorous VOCs were identified using the odor activity value. Compared with laminated boards, particleboards showed higher concentration of total volatile organic compound (TVOC). Halogenated compounds, esters, and aromatic hydrocarbons were main contributors to total VOC emissions, which could relate to the addition of additives used during panel manufacturing. Eleven VOCs were identified that listed as hazardous air pollutants in the US Clean Air Act. Aldehydes were the major contributor to the OAV; most aldehydes have unpleasant odors, such as fatty acids, which contribute to the smell of surrounding air. Octanal was the dominant odorant in the aldehyde compounds.

In southern Chile, epidemiological studies have linked high levels of air pollution produced by the use of wood-burning stoves with the incidence of numerous diseases. Using a quasi-experimental design, this study explores the potential of participatory sensing strategies to transform experiences, perceptions, attitudes, and daily routine activities in 15 households equipped with wood-burning stoves in the city of Temuco, Chile. The results suggest that the experience of using a low-cost sensor improves household members' awareness levels of air pollution. However, the information provided by the sensors does not seem to improve the participants' self-efficacy to control air quality and protect themselves from pollution. The high degree of involvement with the participatory sensing experience indicates that the distribution of low-cost sensors could be a key element in the risk communication policies.

The diet of wood-feeding termites (WFT) consists of cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are utilized by symbiotic protozoa as a carbon source. Protozoa produce acetate, which is the carbon source of the termite. Recently, the mechanisms by which lignin is modified by termites have been reported. Lignin is broken down into its phenylpropanoid monomers and phenolic compounds. Bacteria from WFT gut capable of degrading lignin metabolic products are potentially valuable for bioremediation and biofuel production. A bacterium was isolated from the gut of the WFT and identified as Acinetobacter tandoii. This bacterium was capable of utilizing phenol as the sole carbon source and was able to completely degrade phenol at the concentration of 280 mg/L. A. tandoii degraded phenol via the ortho and β-ketoadipase pathway. This bacterium is a known phenol degrader, but to our knowledge, this is the first time it was isolated and tested for phenol-degrading ability from termites.

The adsorption behavior of basic, methylene blue (MB), and reactive, remazol brilliant violet 5R (RBV), dyes from aqueous solution onto Intsia bijuga sawdust-based activated carbon (IBSAC) was executed via batch and column studies. The produced activated carbon was characterized through Brunauer-Emmett-Teller (BET) surface area and pore structural analysis, proximate and ultimate, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Batch studies were performed to investigate the effects of contact time, initial concentration, and solution pH. The equilibrium data for both MB and RBV adsorption better fits Langmuir model with maximum adsorption capacity of 434.78 and 212.77 mg/g, respectively. Kinetic studies for both MB and RBV dyes showed that the adsorption process followed a pseudo-second-order and intraparticle diffusion kinetic models. For column mode, the breakthrough curves were plotted by varying the flow rate, bed height, and initial concentration and the breakthrough data were best correlated with the Yoon-Nelson model compared to Thomas and Adams-Bohart model. The adsorption activity of IBSAC shows good stability even after four consecutive cycles.

In flexible ethanol-butanol plants, low tolerance to butanol by solventogenic clostridia (and resulting dilute fermentation) results in considerable number of empty fermentors whenever production focuses on ethanol. This research identified scenarios in which vacuum fermentation (in-situ vacuum recovery) may be applied to solve this problem. We conducted ethanol (Saccharomyces cerevisiae) and ABE (Clostridium beijerinckii NCIMB 8052) batch vacuum fermentations of eucalyptus hydrolysates according to the distribution of sugars in a flexible plant. Based on the experiments and performance targets set for the ABE fermentation, we simulated a flexible plant that processes 1000 dry t eucalyptus/day using pretreatment and enzymatic hydrolysis steps with moderate solids loading (15% w/w). The simulation showed that the number of fermentation tanks can decrease by 62% (eliminating 10 idle tanks, 3748 m3 each) by applying vacuum recovery only to the fermentation of mixed (cellulose + hemicellulose) hydrolysates to ABE. We concluded that this configuration can result in savings of up to 2 MMUS$/year in comparison with flexible plants having only conventional batch fermentors, and additional cost savings are expected from reduced wastewater footprint.

Pre-pulping extraction is a means of deriving a hemicellulose-rich process stream from the front end of a kraft pulp mill. When the extraction is carried out using green liquor, pulp quality and quantity can be retained while still releasing hemicelluloses and acetic acid (HAc) for recovery as bioprocessing feedstock or chemical products. The HAc that is present in the wood extraction is inhibitory to microorganisms and can hinder fermentation. HAc is also a commodity chemical that may provide sufficient value to justify recovery and purification. In this study, a liquid-liquid extraction (LLE) method is applied to extract HAc from a green liquor pre-pulping hardwood extract (GLE). The HAc removal is carried out after acid hydrolysis and prior to fermentation. Two organic solutions: trioctylphosphine oxide (TOPO) diluted in undecane and trioctylamine (TOA) diluted in octanol were tested for their abilities to extract HAc from GLE and to be recycled back through the process. GLE was contacted with the organic solvents, phase separated by centrifugation, and the organic phase was then distilled to recover the acetic acid. The solvent was then recycled back for a subsequent extraction of fresh GLE. It was found that TOA was a superior extractant, but failed to easily release its HAc through distillation. It also quickly became contaminated with other compounds in the wood extracts and lost its extraction efficiency after only a few recycles. The TOPO solvent did release its HAc through distillation but also lost extraction capacity with recycling. Back extraction of the TOPO solvent with sodium hydroxide solution restored the performance of the TOPO solvent.

Traditional composting processes must be conducted with a bulking agent to ensure adequate air space for aeration. The bulking agent and composting materials are always completely mixed. A novel layered structure was introduced in sewage sludge composting, in which no bulking agent was used and bamboo charcoal was used as a separating material. Three lab-scale composting reactors (A: sawdust and sludge; B: bamboo charcoal and sludge; and C: sawdust, bamboo charcoal, and sludge) were continuously operated for 29 days. Several physicochemical parameters were investigated to evaluate the feasibility of layered composting with bamboo charcoal. The results indicated that the maximum temperatures during the thermophilic stage in treatments A, B, and C were 51.4, 50.9, and 51 °C, respectively. Layered composting with bamboo charcoal decreased the pH of the thermophilic stage from 8.98 in A to 8.75 in C, and delayed the peaks by about 120 h. The degradation rates of dissolve organic carbon (DOC) and dissolved nitrogen (DN) were 75 and 71.5% in treatment B, respectively, which were significantly higher than those of control group A (60 and 59.1%, respectively). The total NH3 emissions of treatment C (2127.8 mg) were significantly lower than those of A (2522.8 mg). Our results suggested that layered composting using bamboo charcoal as a separating material could be an alternative strategy to the traditional composting method. Moreover, layered composting combined with sawdust could effectively reduce NH3 emissions and N loss.

Around 2.7 billion people in the world cook with polluting fuels, such as wood, crop residue, animal dung, charcoal, coal, and kerosene. Household air pollution from cooking with polluting fuels is recognized as a major risk factor for the disease burden. In this study, we examine the effect of using polluting fuels for cooking on the respiratory health of children in Pakistan. This study uses cross-sectional data from Pakistan Demographic and Health Survey 2012-13, with the sample size of 11,040 children under 5 years of age. Using logistic regression model, we control for factors such as averting activities, child characteristics, household characteristics, mother characteristics, and the unobserved factors using fixed effects. The results show that children in households using polluting fuels are 1.5 times more likely to have symptoms of acute respiratory infection (ARI) than children in households using cleaner fuels.

This study explores the impact of fossil fuels consumption, solid fuels consumption for cooking purposes, economic growth, and carbon emissions on human health, with a key emphasis on the occurrence of tuberculosis and the high mortality rate in Sub-Saharan Africa. For its practical insights, the study develops a system Generalized Method of Moment (GMM) for a panel of 34 middle- and lower-middle-income countries from 1995 to 2015. The study adopts a flexible methodology to tackle endogeneity in the variables. The robust results report that the use of solid fuels (charcoal, peat, wood, wood pellets, crop residues) for cooking purposes and the consumption of fossil fuels (oil, coal, gas) are significantly increasing the occurrence of tuberculosis. In addition, the results highlight that the consumption of both solid fuels and fossil fuels has adverse affects on life expectancy by increasing the mortality rate in Sub-Saharan African countries. Results report that renewable energy sources like sun, wind, and water (all with potential to prevent households from direct exposure to particulate matters and harmful gases) as well as a rise in economic growth serve as helping factors to control the occurrence of tuberculosis and to decrease the mortality rate. Moreover, the use of renewable energy sources is serving to lessen emissions of carbon dioxide, nitrogen dioxides, and particulate matters, which can ultimately decrease the mortality rate and extend the life expectancy in Sub-Saharan Africa.