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1.
Chem Biodivers ; 16(10): e1900397, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31475763

RESUMO

The essential oils from needles, twigs, bark, wood, cones and young shoots of Pinus mugo were analyzed by GC, GC/MS, and 1 H-NMR spectroscopy. More than 130 compounds were identified. The oils differed in the quantitative composition. The principal components of the oil from twigs with needles were 3-carene (23.8 %), myrcene (22.3 %), and α-pinene (10.3 %). The needle oil contained mainly α-pinene (18.6 %), 3-carene (11.3 %), and bornyl acetate (8.3 %). The oils from twigs without needles, young shoots, bark, and wood were dominated by 3-carene (28.6 %, 15.0 %, 18.5 %, and 34.6 %, respectively) and myrcene (23.4 %, 24.0 %, 24.6 %, and 9.4 %, respectively). In the cone oil (E)-ß-caryophyllene was the main constituent (24.0 %).


Assuntos
Óleos Voláteis/isolamento & purificação , Pinus/química , Agulhas , Óleos Voláteis/química , Casca de Planta/química , Brotos de Planta/química , Caules de Planta/química , Polônia , Células Fotorreceptoras Retinianas Cones/química , Madeira/química
2.
J Agric Food Chem ; 67(36): 10137-10144, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423769

RESUMO

Volatile extractive compounds from high-quality oak wood (Quercus sp.) are responsible for important pleasant olfactory notes, such as coconut, wood, vanilla, caramel, and spice. Recently, a new off-flavor reminiscent of rancid butter has been detected in oak wood. Using gas chromatography-olfactometry (GC-O) coupled to several detection modes, such as nitrogen-phosphorus detection (GC-O-NPD) or mass spectrometry (GC-O-MS) and multidimensional GC-O coupled to time-of-flight mass spectrometry, six compounds containing nitrogen atoms were identified. The volatiles were suggested to belong to 2,5-disubstituted pyrazines family, which was confirmed by comparison with synthetic reference compounds. For this purpose, symmetric and dissymmetric 2,5-dialkylpyrazines were prepared from methyl esters of corresponding aliphatic amino acids (Val, Leu, and Ile) by a three-step, one-pot reaction under mild reducing conditions. Organoleptic descriptors and odor detection thresholds were also determined, whereas a bacterial origin explaining these off-flavors was hypothesized.


Assuntos
Aromatizantes/química , Pirazinas/química , Quercus/química , Madeira/química , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria
3.
J Agric Food Chem ; 67(36): 10116-10125, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31442037

RESUMO

Pseudo-lignin is generated from lignocellulose biomass during pretreatment with dilute sulfuric acid and has a significant inhibitory effect on cellulase. However, the mechanism of pseudo-lignin generation remains unclear. The following main points have been addressed to help elucidate the pseudo-lignin generation pathway. Cellulose and xylan were pretreated with sulfuric acid at different concentrations; aliquots were periodically collected; and the changes in the byproducts of the prehydrolysate were quantified. Milled wood lignin (MWL) mixed with cellulose and xylan was pretreated to evaluate the impact of lignin on pseudo-lignin generation. Furfural, 5-hydroxymethylfurfural, and MWL were pretreated as model compounds to investigate pseudo-lignin generation. The result indicated that the increasing acid concentration significantly promoted the generation of pseudo-lignin. When the acid concentration was increased from 0 to 1.00 wt %, pseudo-lignin was increased from 1.36 to 4.05 g. In addition, lignin promoted the pseudo-lignin generation through the condensation between lignin and the generated intermediates.


Assuntos
Lignina/química , Saccharum/química , Ácidos Sulfúricos/análise , Biotecnologia , Celulose/química , Hidrólise , Madeira/química
4.
Bioresour Technol ; 291: 121880, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31374415

RESUMO

This study focused on evaluate the effectiveness of biochar alone compare integrated with bacterial consortium amendment on the gaseous emissions mitigation as well as carbon and nitrogen sequestration during pig manure composting. Six additive treatments were performed based on uniform mixing pig manure with wheat straw [bacterial consortium (T2), 12%wood biochar (T3), 12%wood biochar + bacterial consortium (T4), 12%wheat straw biochar (T5), 12%wheat straw biochar + bacterial consortium (T6), while T1 without any additive]. The results obviously indicated that integrated use of biochar and bacterial consortium could remarkably relieved gaseous emissions, improved carbon and nitrogen conservation as well as accelerated maturity of composting. Notably the optimum combination was existed in T6 owing to lowest nutrient losses (nitrogen and carbon losses were 9.91 g/kg and 189.54 g/kg) and gas emissions (30.16 g/kg) as well as supreme maturity (germination index > 100%); it's an economic-practical and environmental protection novel disposal approach for solid waste.


Assuntos
Carvão Vegetal/metabolismo , Compostagem , Gases/metabolismo , Esterco , Nutrientes , Animais , Carbono/metabolismo , Nitrogênio/análise , Suínos , Triticum/química , Madeira/química
5.
J Agric Food Chem ; 67(35): 9840-9850, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31424924

RESUMO

In the present study, methanolysis of poplar biomass was conducted for the selective transformation of hemicellulose and lignin, which leads to methyl glycosides (mainly C5 glycosides) and lignin fragments in the liquefied products that can be separated according to their difference in hydrophilicity. The distribution of methyl glycosides and delignification was dependent on the presence of acid catalysts and reaction temperatures. The obtained lignin fraction was separated into solid lignin fragments and liquid lignin oil according to their molecular weight distribution. Subsequently, directional conversion of methyl C5 glycosides into methyl levulinate was performed with dimethoxymethane/methanol as the cosolvent. A yield of 12-30% of methyl levulinate yield (based on the methyl glycoside) was achieved under these conditions. The remaining cellulose-rich substrate showed enhanced susceptibility to enzymatic hydrolysis, resulting in a yield of glucose of above 70%. Overall, the described strategy shows practical implications for the effective valorization of biomass.


Assuntos
Fracionamento Químico/métodos , Glucose/isolamento & purificação , Ácidos Levulínicos/isolamento & purificação , Metanol/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Populus/química , Madeira/química , Catálise , Celulose/química , Celulose/isolamento & purificação , Glucose/química , Ácidos Levulínicos/química , Lignina/química , Lignina/isolamento & purificação , Fenóis/química , Extratos Vegetais/química
6.
Chemosphere ; 233: 852-861, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340411

RESUMO

A common strategy to improve indoor air quality in households burning coal and biomass is the introduction of advanced combustion solid fuel stoves, which can use existing fuels yet emit fewer pollutants. Chemical composition of PM is affected by numerous combustion parameters, but is often not considered in energy transitions, despite varying toxicity among chemical components. We analyzed PM2.5 emissions from combustion of solid fuels (coal, wood, and straw; whole and pelletized) in a variety of stoves (cookstoves and heating stoves; traditional and semi-gasifier, including forced versus natural draft and fixed versus reciprocating grate). To assess the effects of fuel and stove type on PM2.5 composition, we measured elemental carbon (EC), organic carbon (OC), water-soluble OC, water-soluble inorganic ions (e.g. SO42-, Cl-, K+), and organic molecular markers. PM2.5 emissions from traditional stoves were mostly carbonaceous: 76-90% organic matter (OM), 5-6% EC, and less than 2% inorganic ions. In contrast, semi-gasifier stoves emitted more inorganic PM2.5: on average, ions comprised 65%, 9% was OM, and 4% was EC. Within the semi-gasifier cookstoves, forced-draft cookstove emissions had lower OM (1-3%) and higher ion concentrations (84-88%) than the natural-draft cookstove (5-14% OM, 30-83% ions). Levoglucosan was detected in PM2.5 from combustion of wood in the traditional cookstove and biomass pellets in the natural-draft semi-gasifier cookstove, but not from wood pellets in the forced-draft semi-gasifier cookstove. Across a range of different fuels and stoves, stove type influenced emitted PM composition more than fuel type, underscoring the impact of combustion conditions on PM chemical composition.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Carbono/análise , Carvão Mineral/análise , Glucose/análogos & derivados , Material Particulado/análise , Biomassa , Culinária , Glucose/análise , Utensílios Domésticos , Produtos Domésticos , Madeira/química
7.
J Agric Food Chem ; 67(33): 9220-9231, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31347838

RESUMO

Slow-release fungicide formulations (azoxystrobin, epoxiconazole, and tebuconazole) shaped as pellets and granules in a matrix of biodegradable poly(3-hydroxybutyrate) and natural fillers (clay, wood flour, and peat) were constructed. Infrared spectroscopy showed no formation of chemical bonds between components in the experimental formulations. The formulations of pesticides had antifungal activity against Fusarium verticillioides in vitro. A study of biodegradation of the experimental fungicide formulations in the soil showed that the degradation process was mainly influenced by the type of formulation without significant influence of the type of filler. More active destruction of the granules led to a more rapid accumulation of fungicides in the soil. The content of fungicides present in the soil as a result of degradation of the formulations and fungicide release was determined by their solubility. Thus, all formulations are able to function in the soil for a long time, ensuring gradual and sustained delivery of fungicides.


Assuntos
Argila/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Fungicidas Industriais/química , Hidroxibutiratos/química , Poliésteres/química , Solo/química , Madeira/química , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Composição de Medicamentos/instrumentação , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Cinética , Pirimidinas/química , Pirimidinas/farmacologia , Estrobilurinas/química , Estrobilurinas/farmacologia , Triazóis/química , Triazóis/farmacologia
8.
J Agric Food Chem ; 67(30): 8402-8410, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31276623

RESUMO

Wines aged in oak wood barrels with various uniform tannin contents (which were classified according to their total ellagitannins contents as predicted by Near Infrared Spectroscopy on the untoasted wood) and different toasting levels (high precision toasting by radiation) were distinguished according to their overall abilities to resist against oxidation. Wine trials were carried out on two different vintages (2015, 2016) and three grape varieties (Sauvignon blanc, Sémillon, Chardonnay). Regardless of the vintage and the wine matrix, a relationship was established between wine oxidative stability (based on EPR spin trapping methodology) and oak barrel tannin potential. The extraction kinetic of ellagitannins by wines appeared linear during barrel aging and achieved its maximum at six or eight months, in a grape variety dependent manner. Oak wood barrel tannin potentials and toastings had no effect on wine glutathione and polyphenols contents. However, wines aged in new barrels with both low and medium tannin potentials, preserved at the end of aging and important number of S-N containing compounds, which was in addition to the known ellagitanins, revealed wines better antioxidant stability.


Assuntos
Antioxidantes/química , Manipulação de Alimentos/instrumentação , Quercus/química , Taninos/análise , Vinho/análise , Madeira/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Fenóis/química , Vitis/química
9.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2274-2277, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359653

RESUMO

Two sesquiterpenes were isolated from the agarwood originating from Gyrinops salicifolia with various chromatographic techniques, and their structures were determined as 12-hydroxy-dihydrocyperolone(1) and(rel)-4ß,5ß,7ß-eremophil-9-en-12,8α-olide(2), through a combined analysis of physicochemical properties and spectroscopic evidence. Compound 1 was a new compound. Compound 2 showed cytotoxicities against K562 and BEL-7401 cell lines, with IC_(50) values of(17.85±0.04) and(21.82±0.07) mg·L~(-1), respectively [taxol as positive control, with IC_(50) values of(1.97±0.11) and(6.31±0.08) mg·L~(-1)].


Assuntos
Sesquiterpenos/farmacologia , Thymelaeaceae/química , Madeira/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Sesquiterpenos/isolamento & purificação
10.
Public Health ; 173: 17-20, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207424

RESUMO

BACKGROUND: This report describes the public health management of an unusual incident involving an increased risk of carbon monoxide (CO) exposure due to the installation of at least 541 wood burners in a local authority area in Wales. PUBLIC HEALTH ACTIONS: An incident management team (IMT) was convened. The IMT assessed and managed the public health risk associated with the wood burners and promoted CO awareness in the local population. OUTCOMES: At least 541 homes were found to have had a wood burner potentially incorrectly installed by a Heating Equipment Testing and Approval Scheme-registered engineer. Local residents were made aware of the dangers and provided with free CO alarms. CONCLUSIONS: This incident highlights that even registered engineers may fail to follow guidelines. It is important to inform the public of the need to have a working CO alarm at home, as well as educating the public and professionals about the symptoms and signs of CO poisoning.


Assuntos
Poluição do Ar/efeitos adversos , Intoxicação por Monóxido de Carbono/etiologia , Monóxido de Carbono , Calefação/efeitos adversos , Saúde Pública , Madeira , Conscientização , Monóxido de Carbono/análise , Intoxicação por Monóxido de Carbono/epidemiologia , Calefação/métodos , Humanos , Administração em Saúde Pública , País de Gales , Madeira/química
11.
J Food Sci ; 84(7): 1692-1702, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31206188

RESUMO

Oak wood is used in barrels for wine aging. During aging, polyphenols are transferred from the barrels to the liquid. Although the bioactivity of oak polyphenols in wines has been extensively studied, no investigation exists on their toxicological properties, which limits their use as functional safe ingredients for other products. In this work, the chemical composition of a polyphenolic extract of Quercus crassifolia bark (QCBe) was studied by GC-MS. Its antibacterial properties on probiotic and pathogenic bacteria and its subacute-oral toxicity were determined as a way to understand the potential impact from its addition to fermented food as a functional ingredient. QCBe shows a selective inhibition of Escherichia coli compared with Lactobacillus bulgaricus and Streptococcus thermophylus. According to the toxicity evaluation, the subacute no-observed-adverse-effect-level was achieved at 11 mg/kg bw/day, whereas the subacute lowest-observed-adverse-effect-level for kidney damage was at 33 mg/kg bw/day. These results suggest that, given the fact an adverse effect was observed after subacute administration of this extract, further longer term toxicological studies are needed to provide sufficient safety evidence for its use in humans. PRACTICAL APPLICATION: Mexico's yogurt market is growing which creates opportunities for the development of some yogurt products as functional foods. As a first step to evaluate its potential use in yogurt formulation, the antibacterial effect of a Quercus crassifolia polyphenolic extract (QCBe) on probiotic bacteria and its subacute-oral toxicity in rats were studied. A low inhibition on probiotic bacteria growth was observed after QCBe addition to Lactobacillus bulgaricus and Streptococcus thermophylus cultures. Exposure to QCBe for a subacute duration resulted in renal injury in rats at dosages greater than or equal to 33 mg/kg/bw/day. This adverse effect indicates the importance of performing further long-term toxicological assessments prior to the addition of QCBe to a food like yogurt, which is regularly eaten by consumers.


Assuntos
Antibacterianos/farmacologia , Casca de Planta/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Quercus/química , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Aditivos Alimentares/química , Aditivos Alimentares/farmacologia , Aditivos Alimentares/toxicidade , Alimento Funcional/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , México , Nível de Efeito Adverso não Observado , Casca de Planta/toxicidade , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Polifenóis/química , Polifenóis/toxicidade , Quercus/toxicidade , Ratos , Vinho/análise , Madeira/efeitos adversos , Madeira/química , Iogurte/análise
12.
Bull Environ Contam Toxicol ; 103(2): 323-329, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230134

RESUMO

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.


Assuntos
Compostagem/métodos , Substâncias Húmicas/análise , Lignina/química , Esterco/análise , Metais Pesados/análise , Solo/química , Animais , Espectrometria de Fluorescência , Suínos , Madeira/química
13.
Food Chem ; 295: 156-164, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174744

RESUMO

During ageing, wood adsorbs volatile compounds from beverages. However, chemical interactions involved in sorption still remain unclear, as well as wood capacity to transfer such compounds to subsequent matrices when reused. Therefore, extractions were conducted from used wood manipulating variables such as ethanol concentration, contact temperature and pH, in order to determine their effect in the interaction and consequent recovery of wine volatiles from wood. Mathematical models were outlined, which demonstrated an exclusive effect of ethanol concentration on the extraction of wine volatiles adsorbed in wood, more prominent for compounds of higher hydrophobicity. Thus adsorption of wine volatiles was shown to be based on hydrophobic interactions. Recovery of wood extractives was also modeled, confirming the known positive effect of ethanol and temperature on the overall extraction of characteristic wood compounds. When reused, wood transferred wine compounds to hydroalcoholic matrices, demonstrating its impact and potential as a vector for aroma transference.


Assuntos
Quercus/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Madeira/química , Adsorção , Etanol/química , Concentração de Íons de Hidrogênio , Temperatura Ambiente , Fatores de Tempo
14.
Environ Sci Process Impacts ; 21(6): 938-949, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31179456

RESUMO

The speciation of radioactive tritium (T) in a naturally-established subtropical loblolly pine forest that has been irrigated with highly-contaminated pond water for the last 20 years is reported. This irrigation project was created to limit the underground transport of a tritium-rich plume which also contains low levels of toxic organics, metals and radionuclides such as carbon-14 (14C) from a nearby low-level waste burial ground. The levels of tritiated water (HTO) in the wood cores were not influenced by recent irrigation activities. However, the tritium levels in the last 20 years of tree growth were more than 3-fold higher than that of tritium in the older growth. This was due to recent irrigation with organic-bound tritium (OBT)-rich water and subsequent accumulation of high levels tritium as OBT relative to tissue HTO. High levels of pond irrigation water OBT resulted from biogenic processes that converted HTO to OBT. Data for 14C that were acquired for some of the forest materials indicated that the processes controlling the movement and accumulation of 14C in this system are somewhat different than that of tritium. Spectroscopic characterization of tree core tissue of <20 years in age found no explanation for the unusually wide dark growth rings. It was concluded that the trees were over-irrigated based on results from other published studies with wood from severely-flooded areas. Although HTO is indeed toxic to biota, OBT represents a relatively greater hazard to biota because it can be bioaccumulated and retained for long periods of time in living tissues.


Assuntos
Pinus/química , Poluentes Radioativos/análise , Trítio/análise , Madeira/química , Radioisótopos de Carbono/análise , Florestas , Monitoramento de Radiação , Poluentes Radioativos/química , Resíduos Radioativos , Trítio/química , Gerenciamento de Resíduos/métodos , Água
15.
Bioresour Technol ; 289: 121675, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31238288

RESUMO

The study highlights one pot conversion of hardwood biomass into Total reducing sugars (TRS) and 5-Hydroxymethyl Furfural (5-HMF). Synergistic effect of dilute H2SO4 and ionic liquid in a reaction time of 60 min at 120 °C was examined. Hydrolysis of Catalpa (Catalpa Bignonioides), Indian Rosewood (Dalbergia Sissoo), Chinaberry (Melia Azedarach) and Babool (Acacia Nilotica) catalyzed by modified activated carbon leads to significant product yield. Maximum yield was obtained using Catalpa wood i.e. 92.67% TRS and 70.36% 5-HMF under optimized conditions. Biomass before and after pretreatment subjected to FT-IR, XRD and compositional analysis determined the structural changes. Further, the effect of electrolytes namely; AlCl3, MgCl2, NaCl and KCl were evaluated. Results revealed that using optimized concentration of each electrolyte promoted the conversion to 96.56% (TRS) and 86.23% (5-HMF) using AlCl3 (4 wt%) for Catalpa wood. Addition of DMSO with optimized electrolyte concentration improves the partition coefficient (3.3) and yield to 88.29% (5-HMF).


Assuntos
Biomassa , Carvão Vegetal/química , Catálise , Hidrólise , Líquidos Iônicos/química , Íons/química , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira/química
16.
Environ Sci Pollut Res Int ; 26(22): 22246-22253, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152421

RESUMO

Sago bark (SB) and empty fruit bunch (EFB) are available abundantly as agricultural waste in Sarawak. This study was conducted to investigate the physicochemical characteristics of SB and EFB as composting materials and used as a plant growth medium. The SB and EFB composts were prepared in a separate container by mixing chicken manure as compost accelerator and wood chips as a bulking agent in dry weight equivalent ratio (1:1:1). The maturity and stability of compost in 60-day composting periods were evaluated via physicochemical characterization of the composts in terms of pH, elemental content, total ash content, moisture content and nutrient analyses. The effect of the compost usage as growth medium was assessed towards water spinach and green mustard via seed germination and pot study. After 2 months, the colour of both composts was dark brown with an earthy smell. The acidic pH of the initial composting stage has changed into alkaline pH after 60 days of composting. Total NPK present in the SB and EFB composts were 0.96% and 1.21%, respectively. The germination index (GI) for the studied vegetables was above 100%, while the pot study showed that vegetables in compost media has higher growth compared to the control, after 14 days. SB and EFB are renewable waste which can be used as an excellent compost and able to improve the quality of the soil.


Assuntos
Mostardeira/crescimento & desenvolvimento , Solo/química , Spinacia oleracea/crescimento & desenvolvimento , Água/análise , Agricultura , Cor , Compostagem , Frutas , Malásia , Esterco/análise , Nutrientes , Casca de Planta , Desenvolvimento Vegetal , Madeira/química
17.
Environ Sci Pollut Res Int ; 26(22): 22688-22703, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172436

RESUMO

Four types of pellets and three agro-fuels were chemically characterised and burned in a pellet stove. To assess the influence of the material composing the firebox and the combustion efficiency of distinct biomass heating devices in the composition of the bottom ashes, three of the pellets were also burned in a conventional woodstove and in a fireplace. Ashes were analysed for their C, H and N contents by an elemental analyser, whilst major and trace elements were quantified by inductively coupled plasma atomic-emission spectrometry and inductively coupled plasma mass spectrometry, respectively. The mineralogy of ashes was determined by X-ray powder diffraction. The European standard test was applied to samples to determine the leaching potential of major, minor and trace elements. The contents of major and trace elements in the different types of biomass presented enormous variations, which are reflected in dissimilar mineralogical and chemical compositions of the respective ashes. The leachable potential of several elements of environmental concern present in oxy-anionic form at the alkaline pH of biomass ashes were generally high in all samples. Concentrations of some elements in the leachates were in the range of values with classification of "hazardous materials" by the European legislation in what respects the acceptance of these wastes at landfills. Pellets made up of wood wastes and containing preservatives (chromated copper arsenate and ammoniacal copper arsenate) are of concern. Due to lower combustion efficiencies, the leachable potential for most of the trace elements in ashes from the woodstove, and especially from the fireplace, was lower than that of the pellet stove.


Assuntos
Cinza de Carvão/química , Biomassa , Modelos Químicos , Oligoelementos/análise , Madeira/química , Difração de Raios X
18.
J Sci Food Agric ; 99(12): 5417-5423, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31077387

RESUMO

BACKGROUND: Smoked fish is a major source of animal protein in developing countries. It is largely produced by hot-smoking on traditional kilns using fuelwood. This practice is associated with high polycyclic aromatic hydrocarbon (PAH) contamination in products, with consequences for public health. An improved kiln, comprising the FAO-Thiaroye Technique (FTT), has been introduced by the Food and Agriculture Organization of the United Nations to address such a concern. The present study investigated the efficacy of the FTT in Ghana through comparative fish smoking experiments with traditional kilns followed by determination of PAH levels [benzo(a)pyrene (BaP) and PAH4] in the products by gas chromatography-mass spectrometry. For each kiln, the effect of smoking fuel type on PAH contamination was determined. The impact of the design characteristics of the FTT on the levels of the compounds was also determined. RESULTS: Mean BaP and PAH4 levels in the FTT products were up to 1.8 and 7.6 µg kg-1 , respectively, whereas the corresponding levels in traditional kiln products were up to 70 and 395 µg kg-1 . PAH levels in FTT products were below European Union regulatory limits, whereas levels in traditional kiln products exceed such limits by up to 33-fold. Across kiln types, the use of wood fuels caused higher PAH contamination compared to the use of fully-lit charcoal as an alternative fuel. CONCLUSION: The improved kiln (FTT) is efficacious in yielding smoked fish with a PAH content lower than the levels in traditional kiln products and also below current regulatory limits. Kiln design and type of processing fuel have significant impacts on PAH contamination during fish smoking. © 2019 Society of Chemical Industry.


Assuntos
Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Conservação de Alimentos/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Benzo(a)pireno/análise , Carvão Vegetal/efeitos adversos , Carvão Vegetal/análise , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Cromatografia Gasosa-Espectrometria de Massas , Gana , Madeira/efeitos adversos , Madeira/química
19.
Environ Sci Pollut Res Int ; 26(19): 19598-19605, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077053

RESUMO

The ability of standard soils to capture heavy metals or polycyclic aromatic hydrocarbons (PAHs) from ammoniacal copper zinc arsenate (ACZA)- or creosote-treated wood, respectively, was assessed using pressure-treated posts immersed in a freshwater pond. The soil, in heat-sealed, permeable plastic mesh sachets, was able to intercept copper, zinc, arsenic, and PAHs migrating from the posts. Chemical levels were much higher immediately adjacent to the posts and declined with distance from the posts. Metals were consistently detected around ACZA-treated posts, while 10 of the 16 EPA priority pollutants were detected in at least one sachet embedded around creosote-treated posts at each sampling point. These results were consistent with traditional sediment sampling methods. The primary advantages of the sachets were their consistency in terms of soil characteristics and the ease with which they could be retrieved from the pond. Further studies are planned to better understand the role of soil characteristics in the sachets on the ability to capture migrating preservatives.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , Madeira/química , Arseniatos/análise , Cobre/análise , Creosoto/análise , Recuperação e Remediação Ambiental/instrumentação , Desenho de Equipamento , Polímeros/química , Zinco/análise
20.
Environ Pollut ; 251: 312-327, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31091495

RESUMO

In China, the huge amounts of energy consumption caused severe carcinogenic polycyclic aromatic hydrocarbon (PAHs) concentration in the soil and ambient air. This paper summarized that the references published in 2008-2018 and suggested that biomass, coal and vehicular emissions were categorized as major sources of PAHs in China. In 2016, the emitted PAHs in China due to the incomplete combustion of fuel was about 32720 tonnes, and the contribution of the emission sources was the sequence: biomass combustion > residential coal combustion > vehicle > coke production > refine oil > power plant > natural gas combustion. The total amount of PAHs emission in China at 2016 was significantly decreased due to the decrease of the proportion of crop resides burning (indoor and open burning). The geographical distribution of PAHs concentration demonstrated that PAHs concentration in the urban soil is 0.092-4.733 µg/g. At 2008-2012, the serious PAHs concentration in the urban soil occurred in the eastern China, which was shifted to western China after 2012. The concentration of particulate and gaseous PAHs in China is 1-151 ng/m3 and 1.08-217 ng/m3, respectively. The concentration of particle-bound PAHs in the southwest and eastern region are lower than that in north and central region of China. The incremental lifetime cancer risk (ILCR) analysis demonstrates that ILCR in the soil and ambient air in China is below the acceptable cancer risk level of 10-6 recommended by US Environmental Protection Agency (EPA), which mean that there is a low potential PAHs carcinogenic risk for the soil and ambient air in China.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Emissões de Veículos/análise , China , Carvão Mineral/análise , Gasolina/análise , Medição de Risco , Madeira/química
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