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1.
J Environ Manage ; 261: 110246, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148312

RESUMO

Reclamation of degraded soils such as those with low organic carbon content and soils co-contaminated with toxic elements and phthalic acid esters (PAEs) is of great concern. Little is known about the efficiency of plant- and animal-derived biochars for improving plant growth and physicochemical and biological properties of co-contaminated soils, particularly under low content of organic matter. Hence, a pot trial was carried out by growing pak choi (Brassica chinensis L.) to assess the influence of different doses (0, 0.5, 1, 2, and 4%) of animal (pig carcass) and wood (Platanus orientalis) derived biochars on soil properties, nutrient availabilities, plant growth, and soil enzyme activities in two soils containing low (LOC) and high (HOC) organic carbon contents and co-contaminated with di-(2-ethylhexyl) phthalic acid (DEHP) and cadmium (Cd). Biochar applications improved pH, salinity, carbon content, and cation exchange capacity of both soils. Addition of biochars significantly increased the bioavailability and uptake of phosphorus and potassium in the plants in both soils with greater effects from pig biochar than wood biochar. Biochar additions also significantly enhanced urease, sucrase, and catalase activities, but suppressed acid phosphatase activity in both soils. The impact of pig biochar was stronger on urease and acid phosphatase, while the wood biochar was more effective with sucrase and catalase activities. The biomass yield of pak choi was significantly increased after biochar addition to both soils, especially in 2% pig biochar treatment in the LOC soil. The positive response of soil enzymes activities and plant growth for biochar addition to the Cd and DEHP co-contaminated soils indicate that both biochars, particularly the pig biochar can mitigate the risk of these pollutants and prove to be eco-friendly and low-cost amendments for reclaiming these degraded soils.


Assuntos
Poluentes do Solo , Solo , Animais , Disponibilidade Biológica , Carvão Vegetal , Metais , Ácidos Ftálicos , Suínos , Madeira
2.
Waste Manag ; 105: 457-466, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32135467

RESUMO

Biochar from agricultural biomasses and solid wastes represents a win-win solution for a rational waste management. Its sustainable usage requires the identification and standardization of biochar characteristics. The aim of this work was to identify the physical-chemical and spatial characteristics of biochars from pruning residues (PR), poultry litter (PL), and anaerobic cattle digestate (CD) at two pyrolysis temperatures (350 °C and 550 °C). The biochar characterization was carried out by applying emerging imaging techniques, 2D automated optical image analysis and hyperspectral enhanced dark-field microscopy (EDFM), and by SEM analysis. As predictable, the feedstock composition and the pyrolysis temperature strongly influence the physical structures of the biochar samples. Irrespective of charring temperature, PR biochar was mainly characterized by a broken and fragmented structure with an irregular and rough particle surface, completely different from the original PR wood cell. The EDFM imaging analysis evidenced the thermal degradation of PR vegetal products, composed primarily of hemicellulose, cellulose and lignin. On the contrary, small and regular particles with a smooth surface were produced by the PL pyrolysis, especially at 550 °C, due to the lower PL morphological homogeneity in comparison with the other biomasses. Finally, CD charring at both temperatures was characterized by changes in chemical composition, suggested by a lower pixel intensity. In conclusion, the emerging imaging techniques used in this study proved to be very effective in analyzing some properties of biochars, and can, therefore be considered as promising experimental strategies for detecting the feedstock and pyrolysis temperature of biochar.


Assuntos
Carvão Vegetal , Microscopia , Animais , Bovinos , Temperatura Ambiente , Madeira
3.
Waste Manag ; 105: 560-565, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32163835

RESUMO

The paper examines the process of carbonization of waste from corncobs at carbonization temperatures within a range of 300-700 °C in a laboratory-scale reactor. These studies are important because of reductions in wood resources for the preparation of barbecue charcoal due to environmental protection laws and legislative processes in many countries aimed at the protection of forest resources. The results presented here include the physical and chemical properties of char as a function of carbonization temperatures as well as the characteristics of the heating rate of a fixed bed of corncobs and within a single corncob particle. The combustion characteristics of the char were determined using thermogravimetric analysis. The results show that the volatile matter yield of the char decreased, whereas the fixed carbon yield and higher heating value (HHV) increased, along with higher carbonization temperatures. TGA analysis shows that the ignition and burnout temperature of the char increased, with a simultaneous decrease in the value of the S index, along with increased carbonization temperatures. The results show that carbonization temperatures of 500 °C and above meet the standards for the production of barbecue charcoal.


Assuntos
Carvão Vegetal , Zea mays , Carbono , Temperatura Ambiente , Madeira
4.
Trends Plant Sci ; 25(4): 322-324, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32191868

RESUMO

Lignin enhances the mechanical strength of plants and enables their intrinsic water transport. Dendrochronological, wood anatomical, and plant physiological evidence now suggests that the degree of lignin deposition is constrained by low temperature. Placing these findings in an ecological context implies rethinking of the global treeline position.


Assuntos
Parede Celular , Lignina , Membrana Celular , Plantas , Madeira
5.
Science ; 367(6484): 1305-1306, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32193311
6.
Bioresour Technol ; 302: 122795, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004810

RESUMO

To elevate the glucose yield from the enzymatic hydrolysis of poplar wood for bio-ethanol production, quick hydrothermal treatment (QHT) was conducted at 200 °C for a short period of time from 5 min to 25 min. It was found that the QHT could remove >85% of the hemicelluloses and ~30% of the lignin in the poplar wood, and achieve 82% cellulose conversion at a low cellulase dosage of 10 FPU/g substrate. The enhancement digestibility of poplar wood was ascribed to the higher accessibility of cellulose, as the specific surface area of the substrate increased from 3.0 m2/g to 7.1 m2/g from the of untreated wood to the QHT-treated wood. The results demonstrate the improvements in digestibility and hydrolysis rates after QHT.


Assuntos
Celulase , Populus , Hidrólise , Lignina , Madeira
7.
Bioresour Technol ; 302: 122895, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32019706

RESUMO

Over the last century the pulp and paper sector has assessed various technologies to fractionate woody biomass to produce strong, bright fibers. Several of these processes have also been assessed for their potential to pretreat and fractionate biomass to enhance the subsequent enzymatic hydrolysis of the cellulosic component. Although many of these pretreatments are effective on agricultural residues, softwoods have proven more recalcitrant, primarily due to their high lignin content and structure. As delignification is too expensive to be used routinely a more economically attractive approach might be to alter the lignin. Recent work has shown that, using a modified chemithermomechanical pulping (CTMP) "front end", lignin can be modified and relocated. This significantly enhanced hemicellulose recovery and enzyme-mediated cellulose hydrolysis of woody biomass. As well as being effective on wood chips, the modified CTMP pretreatment process also enhanced the bioconversion of densified feedstocks such as pellets.


Assuntos
Lignina , Madeira , Biomassa , Celulose , Hidrólise
8.
Environ Sci Technol ; 54(5): 2565-2574, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32022554

RESUMO

We developed a method to better estimate the carbon stocks of in-use harvested wood products (HWP) by using the Eora multiregional input-output tables to link global HWP production and end uses, compared to existing global-scale studies that focused on semifinished HWP. Using the new method, we allocated global HWP to country-specific end uses, including solid HWP used in (1) construction, (2) furniture production, and (3) other end uses, and as (4) household and sanitary paper and (5) other paper and paper products, while the HWP carbon stocks in these end uses were estimated using the Stock Change Approach. We reported that HWP produced globally contained an annual average of 277.7 teragram carbon in 1992-2015, of which 63.0, 12.6, 76.7, 9.1, and 116.3 teragram carbon were consumed by the above five end uses, respectively. By 2015, the carbon stocks of global in-use HWP produced since 1992 accumulated to 2938 teragrams of carbon, of which the above five HWP end uses accounted for 1489, 268, 890, 0, and 291 teragrams of carbon, respectively. Country-specific HWP production and consumption varied significantly, with the eight leading consuming countries (United States, China, Japan, Canada, Germany, Russia, United Kingdom, and France) accounting for 69% of the global in-use HWP carbon stocks.


Assuntos
Carbono , Madeira , Canadá , China , França , Alemanha , Japão , Federação Russa , Reino Unido
9.
Science ; 367(6484): 1385-1390, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32054697

RESUMO

The profitability and sustainability of future biorefineries are dependent on efficient feedstock use. Therefore, it is essential to valorize lignin when using wood. We have developed an integrated biorefinery that converts 78 weight % (wt %) of birch into xylochemicals. Reductive catalytic fractionation of the wood produces a carbohydrate pulp amenable to bioethanol production and a lignin oil. After extraction of the lignin oil, the crude, unseparated mixture of phenolic monomers is catalytically funneled into 20 wt % of phenol and 9 wt % of propylene (on the basis of lignin weight) by gas-phase hydroprocessing and dealkylation; the residual phenolic oligomers (30 wt %) are used in printing ink as replacements for controversial para-nonylphenol. A techno-economic analysis predicts an economically competitive production process, and a life-cycle assessment estimates a lower carbon dioxide footprint relative to that of fossil-based production.


Assuntos
Alcenos , Pegada de Carbono , Fenóis , Madeira , Biomassa , Carboidratos , Catálise , Fracionamento Químico , Lignina , Fenol
10.
Plant Dis ; 104(3): 702-707, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31958250

RESUMO

Silverleaf caused by the basidiomycete Chondrostereum purpureum affects numerous woody species, including fruit tree crops like apple, resulting in wood necrosis and foliar silvering. There are no curative alternatives for this disease, and its management is by prevention methods. Therefore, the aim of this study was to develop a rapid diagnostic tool for the detection and identification of C. purpureum directly from woody tissues to help distinguish the pathogen from other basidiomycetes that are commonly found on apple. The silverleaf pathogen was isolated from different hosts and locations, and Koch's postulates were performed by inoculating the isolates on apple cuttings and measuring internal necrosis. A previously described APN 1 pair of primers specificity was also tested against 25 C. purpureum isolates in this study, using other wood rotting species as negative controls. Seven virulent isolates were inoculated on apple cuttings, and DNA was extracted from the cuttings' sawdust and amplified using APN 1, after 22 days of incubation. To prove the efficiency of the method in the field, DNA from healthy nursery plants inoculated with two virulent isolates, and naturally infected plants showing different levels of foliar symptoms, were tested. Presence of the fungus was verified by reisolation on APDA in all assays. Koch's postulates indicated that all C. purpureum isolates were pathogenic, showing different virulence levels, and APN 1 primers were able to discriminate them from other basidiomycetes. The method was also able to detect C. purpureum from artificially inoculated plants as well as naturally infected ones, demonstrating that the protocol may become a rapid minimally destructive diagnostic tool to detect the pathogen without the need to isolate it from tissues, and thus taking measures to prevent its dissemination.


Assuntos
Agaricales , Malus , Frutas , Reação em Cadeia da Polimerase , Madeira
11.
Environ Monit Assess ; 192(2): 104, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915931

RESUMO

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.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Chile , Cidades , Participação da Comunidade , Monitoramento Ambiental/instrumentação , Humanos , Madeira/química
12.
Bioresour Technol ; 300: 122652, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918299

RESUMO

Recycled wood of two grades (A and B) and spruce were converted on bench (100 o.d. g) and pilot (100 o.d. kg) scales to monosugars, lignin and lignosulfonates using SO2-Ethanol-Water (AVAP®) technology. After digestion, C6 and C5 sugars were recovered at 98-100% and 87-99% for Wood A and Spruce, respectively, while the values for Wood B were 92% and 74-87%. Cellulose was hydrolysed to glucose at 90% or higher using enzyme charge of 7.1 FPU/g glucan. Hemicellulosic sugars were autohydrolyzed to 95-100% monosugars. At bench scale, monosaccharide yield was 609, 561 and 688 kg (hydrous) per BDT biomass for Wood A, Wood B and Spruce, respectively. Corresponding water insoluble lignin yield was 157, 148 and 189 kg per BDT biomass. The preliminary techno-economic evaluation revealed that conversion of recycled wood to sugars using AVAP® fractionation platform results in higher profitability in comparison to virgin wood.


Assuntos
Lignina , Madeira , Biomassa , Etanol , Hidrólise , Lignina/análogos & derivados , Açúcares , Dióxido de Enxofre , Água
13.
Bioresour Technol ; 300: 122657, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918300

RESUMO

Organosolv is a promising pretreatment for lignocellulose biorefinery on the integrated utilization of full components from lignocellulosic biomass. A highly efficient pretreatment process using methanol/dioxane binary solvent with microwave irradiation is proposed in this study. Poplar wood was fractionated to high quality cellulosic residue, lignin, and monosaccharide derivatives under mild conditions (120 °C, 10 min). The follow-up enzymatic hydrolysis of resulting cellulosic residues achieved almost theoretical glucan conversion over 99%. The 2D-NMR and GPC results showed that the recovered lignin precipitates contain low amount of condensed structures and have relatively narrow molecular weight distributions. The composition analysis of monosaccharide derivatives indicated that the methanol/dioxane solvent tends to convert monosaccharides into glycosides rather than further degradation by-products. The mass balance result estimated that totally 74.2% of raw poplar can be utilized by the pretreatment proposed in this study.


Assuntos
Metanol , Madeira , Biomassa , Dioxanos , Hidrólise , Lignina , Micro-Ondas , Solventes
14.
Bioresour Technol ; 300: 122623, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927344

RESUMO

Microbial fuel cell is a green and sustainable bio-electrochemical system that can harvest bioelectricity from organic matter conversion by bacteria in wastewater, but weak electrochemical activity and poor biocompatibility between electro-active bacteria and anode limit its scale-up application. In the present, the biomass carbon derived from mango wood was prepared via one-step carbonization method for anode materials in microbial fuel cell. A desirable anode C/1050 with large electrochemical active surface area (75.3 cm2), low electron transfer resistance (4.36 Ω), and benign biocompatibility were developed, achieving power density up to 589.8 mW·m-2. This study provides a low-cost and high-performance biomass carbon used as anode material in microbial fuel cell for practical application.


Assuntos
Fontes de Energia Bioelétrica , Mangifera , Biomassa , Carbono , Eletricidade , Eletrodos , Madeira
15.
Bioresour Technol ; 301: 122619, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31931333

RESUMO

This work studies the chemical kinetics of wood pyrolysis by comparing nine reduced reaction schemes against 22 microscale experiments of softwood and hardwood from the literature. The complexity of reaction schemes ranged from 1 to 12 reactions, with 2 to 7 species. Using multi-objective optimization for isothermal and non-isothermal conditions, the kinetic parameters for each reaction scheme were derived. It was found that the uncertainty of a prediction increases with the number of model parameters, but the accuracy does not always increase with the number of parameters. The appropriate reaction scheme for hardwood is three parallel reactions, as it presents the optimal balance between accuracy and uncertainty. For softwood, a higher complexity could be justified. This work shows the benefits of finding an appropriately complex kinetic scheme by building up complexity from simple schemes.


Assuntos
Pirólise , Madeira , Cinética
16.
Bioresour Technol ; 301: 122720, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945685

RESUMO

This study might be the first to explore the novel constructed microbial consortia CS-5 and BC-4 for enhancing methane (CH4) production during anaerobic digestion (AD) with simultaneous degradation of catalpa sawdust and chlorophenols (CPs). Significant reduction in cellulose, hemicellulose and lignin contents was achieved after the biodegradation of catalpa sawdust for 15 days by CS-5 and BC-4, with a total weight loss of 69.2 and 56.3%, respectively. The synergistic microbial consortia enhanced cumulative biogas and CH4 yields by 76.3 and 64.3%, respectively higher than the corresponding control at the end of AD. More than 90% of CH4 was produced within 18 days of AD as a result of microbial pretreatment of catalpa sawdust. These consortia resulted in remarkably higher energy conversion efficiency of 44.3% (218.1 LN CH4/kg TS) over the control. CS-5 and BC-4 removed more than 69 and 77% of the total amount of CPs tested after 15 days.


Assuntos
Clorofenóis , Consórcios Microbianos , Anaerobiose , Biocombustíveis , Lignina , Metano , Madeira
17.
Chemosphere ; 242: 125255, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896180

RESUMO

A woody-biochar was added to waste biomass during a composting process. The resulting compost-char was amended to a metal contaminated soil and two plant species, L. perenne and E. sativa, were grown in a pot experiment to determine 1) plant survival and stress factors, 2) uptake of metals to plants and, 3) chemical characteristics of sampled soils and pore waters. Compost supplemented with biochar after the composting process were also tested, as well as a commercially available compost, for comparison. Co-composting with biochar hastened the composting process, resulting in a composite material of reduced odour, increased maturity, circum-neutral pH and increased moisture retention than compost (increase by 3% of easily removable water content). When amended to the soil, CaCl2 extractable and pore water metals s were reduced by all compost treatments with little influence of biochar addition at any tested dose. Plant growth success was promoted furthest by the addition of co-composted biochar to the test soil, especially in the case of E. sativa. For both tested plant species significant reductions in plant metal concentrations (e.g. 8-times for Zn) were achieved, against the control soil, by compost, regardless of biochar addition. The results of this study demonstrate that the addition of biochar into the composting process can hasten the stability of the resulting compost-char, with more favourable characteristics as a soil amendment/improver than compost alone. This appears achievable whilst also maintaining the provision of available nutrients to soils and the reduction of metal mobility, and improved conditions for plant establishment.


Assuntos
Brassicaceae/crescimento & desenvolvimento , Carvão Vegetal/química , Compostagem , Lolium/crescimento & desenvolvimento , Metais/análise , Madeira/química , Biodegradação Ambiental , Biomassa , Brassicaceae/química , Lolium/química , Modelos Teóricos , Solo/química , Poluentes do Solo/análise
18.
Ying Yong Sheng Tai Xue Bao ; 31(1): 259-265, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957403

RESUMO

Wood-decaying fungi are important components of forest ecosystem, mainly growing on the dead wood and decomposing lignin, cellulose, and hemi-cellulose. Understanding the ecological distribution of wood-decaying fungi are necessary to reveal their ecological function. In this study, we investigated wood-decaying fungi at three sites with different altitudes in Laojunshan National Park. Fruit bodies of fungi were collected and identified based on morphological and molecular analy-sis. In total 68 species were recorded, belonging to 40 genera, 21 families and 8 orders. Polyporaceae, Fomitopsidaceae, and Hymenochaetaceae were dominant families. The floral composition showed a distinct north temperate character, which was the most important element among all the bio-geographical elements with the highest percentage of 38.2%. These wood-decaying fungi can be divided into two ecological types: saprophytic (63 species) and ectomycohizal (5 species). Among these saprophytic fungi, 51 species could cause white rot and 12 species cause brown rot. The amounts of fungal species in deciduous broad-leaf forest (DBF), coniferous broad-leaved mixed forest (CBMF) and dark coniferous forest (DCF) were 34, 26 and 22, respectively. Postia fragilis and Stereum hirsutum, distributed in all the three types of forests, were dominant species of Laojunshan National Park.


Assuntos
Ecossistema , Madeira , China , Fungos , Parques Recreativos
19.
Bioresour Technol ; 300: 122622, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31891856

RESUMO

Simultaneous enzymatic saccharification and comminution (SESC) was used for large-scale anaerobic digestion of wood lignocellulose to generate methane and unmodified lignin. During SESC, 10% aqueous mixture of powdered debarked wood from various species was subjected to bead milling with hydrolytic enzymes to generate particles below 1 µm. This slurry was directly used as a cosubstrate for anaerobic digestion in a 500 L stirred-tank reactor. Temperature and hydraulic retention time (HRT) were maintained at 50 °C and 30 days, respectively. At stable operation periods, an average yield of 224 L of methane per kg of cedar was attained. Comparable yields were achieved with red pine, elm, oak, and cedar bark. High-throughput microbial analysis established the presence of a relevant community to support the elevated level of methane production. The stability of the unmodified lignin in anaerobic digestion was also confirmed, allowing for its recovery as an important by-product.


Assuntos
Lignina , Esgotos , Anaerobiose , Reatores Biológicos , Metano , Madeira
20.
Bone Joint J ; 102-B(1): 48-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31888371

RESUMO

AIMS: Distal radial fractures are the most common fracture sustained by the adult population. Most can be treated using cast immobilization without the need for surgery. The aim of this study was to assess the feasibility of a definitive trial comparing the commonly used fibreglass cast immobilization with an alternative product called Woodcast. Woodcast is a biodegradable casting material with theoretical benefits in terms of patient comfort as well as benefits to the environment. METHODS: This was a multicentre, two-arm, open-label, parallel-group randomized controlled feasibility trial. Patients with a fracture of the distal radius aged 16 years and over were recruited from four centres in the UK and randomized (1:1) to receive a Woodcast or fibreglass cast. Data were collected on participant recruitment and retention, clinical efficacy, safety, and patient acceptability. RESULTS: Over an eight-month period, 883 patients were screened, 271 were found to be eligible, and 120 were randomized. Patient-reported outcome measures were available for 116 (97%) of participants at five weeks and 99 (83%) at three months. Clinical outcomes and patient acceptability were similar between the two interventions and no serious adverse events were reported in either intervention arm. CONCLUSION: Both interventions were deemed efficacious and safe in the cohort studied. This study showed that a definitive study comparing Woodcast and fibreglass was feasible in terms of patient recruitment and retention. Cite this article: Bone Joint J 2020;102-B(1):48-54.


Assuntos
Moldes Cirúrgicos , Imobilização/instrumentação , Fraturas do Rádio/terapia , Adolescente , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Imobilização/métodos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Segurança do Paciente , Resultado do Tratamento , Madeira , Adulto Jovem
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