Influence of carbonization temperature on the anatomical characteristics of Ocotea porosa (Nees & Mart. Ex Nees) L. Barroso     

Silvana Nisgoski  Graciela Inés Bolzon de Muñiz  Francielli Rodrigues Ribeiro Batista  Richard Eduard Mölleken 《Wood Science and Technology》2014,48(2):301-309

The carbonization process causes different physical and chemical transformations to wood, affecting the final properties of the charcoal produced. In Brazil, the cutting and use of Ocotea porosa (Nees & Mart. Ex Nees) L. Barroso is legally prohibited. But the difficulty of identifying the species used to produce charcoal hinders enforcement efforts to protect this and other endangered tree species. The aim of this work was to characterize the anatomy of charcoal made from O. porosa at different temperatures to provide information to facilitate differentiation of the species by the authorities in charge of suppressing illegal commerce. Samples were carbonized by direct heating and final temperatures of 350, 450 and 650 °C, besides a group under a ramp heating regime also with a final temperature of 450 °C. The qualitative characteristics of the O. porosa wood were preserved at the carbonization temperatures studied permitting the use of its anatomical structures for identification of carbonized wood to support control of the illegal trade in charcoal of this species.  相似文献   

Effect of soil bacteria on the ability of polycyclic aromatic hydrocarbons (PAHs) removal by Trametes versicolor and Irpex lacteus from contaminated soil     

Eduard Borràs  Gloria Caminal  ?enek Novotný 《Soil biology & biochemistry》2010,42(12):2087-2093

The effect of bacteria represented by indigenous soil microflora or a mixture of soil bacteria Pseudomonas aeruginosa and Rhodococcus erythropolis on fungal growth, extracellular enzyme production and polycyclic aromatic hydrocarbons (PAHs) biodegradation efficiency in soil of white-rot fungi Trametes versicolor and Irpex lacteus was investigated. Both fungi were able to colonize soil. The growth yields measured by ergosterol were about two-fold in I. lacteus after 10 weeks. Laccase was produced in T. versicolor cultures in the presence or absence of bacteria but live bacteria reduced the laccase levels in soil about 5 times. Manganese-dependent peroxidase (MnP) was not detected in T. versicolor cultures. The amounts of MnP and laccase in I. lacteus cultures were not affected by the presence of bacteria. T. versicolor was more efficient in PAH removal for all PAHs tested although its capacity to colonize soil was lower. The removal rates of PAHs by T. versicolor in sterile soil were 1.5-fold, 5.8-fold and 1.8-fold for 2-3-ring, 4-ring and 5-6-ring PAHs, compared to I. lacteus, respectively. I. lacteus showed a low efficiency of removal of pyrene, benzo[a]anthracene and benzo[k]fluoranthene, compared to T. versicolor, whereas chrysene and benzo[b]fluoranthene were degraded by neither fungus. The main effect of the presence of the indigenous microflora or R. erythropolis and P. aeruginosa was a significant decrease of degradation of total PAHs by both T. versicolor and I. lacteus. Weak fungal/bacterial synergistic effects were observed in the case of removal of acenapthylene, benzo[a]pyrene, dibenzo[a,h]anthracene and benzo[g,h,i]perylene by I. lacteus and acenapthylene by T. versicolor. However, the bacterial effects were different in the two fungi. PAH abiotic losses represented 15 and 21% of the total PAHs after 5 and 10 weeks, respectively; naphthalene and acenaphthene were removed from the soil due to volatilization.  相似文献   

Correcting the Effect of the Sorbent to Solution Ratio on Sorption Isotherms from Batch Tests with Soils and Sediments     

Kay-Uwe Fehse  Heinz Borg  Eduard Sorkau  Kurt Pilchowski  Ludwig Luckner 《Water, air, and soil pollution》2010,210(1-4):211-220

There is evidence in the literature that the ratio of mass of sorbent (M) to volume of solution (V) affects the results of batch tests with soils and sediments. This restricts the use of such data to conditions with the same M/V ratio they were derived with, unless its influence is corrected. To find a correction, we conducted batch tests with soil and zinc solution using four M/V ratios. For each ratio, the experiments produced a different relationship between the mass of zinc sorbed per unit mass of soil (a _s) and the zinc concentration in the solution after shaking and removal of the solid phase (C _det), which is usually taken as the equilibrium concentration (C _eq). A theoretical analysis revealed that the M/V effect can be accounted for by dividing C _det by the M/V ratio, if it is caused by the presence of a “third phase”. The relationship between a _s and C _det×V/M is the same for all ratios then.  相似文献   

Ingestion of starch-rich meals after exercise increases glucose kinetics but fails to enhance muscle glycogen replenishment in horses     

Jose-Cunilleras E  Hinchcliff KW  Lacombe VA  Sams RA  Kohn CW  Taylor LE  Devor ST 《Veterinary journal (London, England : 1997)》2006,171(3):468-477

Fatiguing exercise substantially decreases muscle glycogen concentration in horses, impairing athletic performance in subsequent exercise bouts. Our objective was to determine the effect of ingestion of starch-rich meals after exercise on whole body glucose kinetics and muscle glycogen replenishment. In a randomized, cross-over study seven horses with exercise-induced muscle glycogen depletion were either not fed for 8 h, fed half of the daily energy requirements ( approximately 15 Mcal DE) as hay, or fed an isocaloric amount of corn 15 min and 4 h after exercise. Starch-rich meals fed after exercise, when compared to feed withholding, resulted in mild to moderate hyperglycemia (5.7+/-0.3 vs. 4.7+/-0.3 mM, P<0.01) and hyperinsulinemia (79.9+/-9.3 vs. 39.0+/-1.9 pM, P<0.001), 3-fold greater whole body glucose kinetics (15.5+/-1.4 vs. 5.3+/-0.4 micromol kg(-1)min(-1), P<0.05), but these only minimally enhanced muscle glycogen replenishment (171+/-19 vs. 170+/-56 and 260+/-45 vs. 294+/-29 mmol/kg dry weight immediately and 24 h after exercise, P>0.05). It is concluded that after substantial exercise-induced muscle glycogen depletion, feeding status only minimally affects net muscle glycogen concentrations after exercise, despite marked differences in soluble carbohydrate ingestion and availability of glucose to skeletal muscle.  相似文献   

Magnetic Signature of Industrial Pollution of Stream Sediments and Correlation with Heavy Metals: Case Study from South France     

Desenfant  Fabrice  Petrovský  Eduard  Rochette  Pierre 《Water, air, and soil pollution》2004,152(1-4):297-312

Industrial pollution is one of the most important environmentalthreats, with serious consequences for the future. Thus, its detailed study is of great importance. Apart from expensive andtime-consuming chemical methods, several rapid and cheap proxymethods have been developed recently, one of them being based on rock-magnetic parameters. In the present paper we examine the use of rock-magnetic methods designed to assess the degree of pollution of recent stream sediments taken from the Arc river (Provence, France). The aim was to identify industrially-derived magnetic particles and to link this `magnetic pollution' to concentrations of heavy metals. Geological basements allow the easy determination of magnetic particles of industrial origin. Our results clearly demonstrate that magnetic anomalies, observed in the stream sediments along the river, can be explained by human activities, as they correlate well with concentrations of lead, zinc, iron and chromium.  相似文献   

Increased hippuric acid content of urine can reduce soil N₂O fluxes     

Dorien M. Kool  Eduard W.J. Hummelink 《Soil biology & biochemistry》2006,38(5):1021-1027

Urine patches in grazed pastures are a major source of nitrous oxide (N₂O) emission. It is well-documented that the relative concentration of the various nitrogenous urine constituents varies significantly with diet. The effect of these variations on N₂O emissions from urine patches, however, has never been reported. The aim of this study was to test whether variations in urine composition, consistent with different diets, lead to significant differences in N₂O emission. Four varieties of artificial urine, all with similar total N concentrations, but varying in the relative contribution of the nitrogenous constituents, were applied to undisturbed cores from a sandy pasture soil. N₂O fluxes were monitored for 65 days at two moisture treatments; 92% WFPS for the entire incubation, and 70% WFPS up to day 41 and 92% afterwards. Extra replicates were included for destructive analysis on mineral N concentrations and pH. Urine composition was a significant (P<0.001) factor determining N₂O emissions. An increase in the relative hippuric acid concentration from 3 to 9% of total N resulted in a significant decline in average N₂O fluxes, from 16.4 to 8.7 μg N₂O-N h⁻¹ kg⁻¹ soil (averaged over all treatments). Cumulative emission decreased from 8.4 to 4.4% of the applied urine-N (P<0.01). Soil mineral N showed a modest but significant decrease with an increase of hippuric acid content. pH did not show any significant relationship with urine composition. Increasing the urea concentration with 12% of applied urinary N did not significantly affect N₂O emissions. Moisture content significantly affected N₂O emissions (P<0.001), but no interaction between moisture and urine composition was found. As the inhibitory effect of hippuric acid could not be linked directly to mineral N concentrations in the soil, we hypothesize that the breakdown product benzoic acid either inhibits denitrification or decreases the N₂O/N₂ ratio. We conclude that hippuric acid concentration in urine is an important factor influencing N₂O emission, with a potential for reducing emissions with 50%. We suggest alternative rationing leading to higher hippuric acid concentrations in urine as a possible strategy to mitigate N₂O emission from grazed pastures.  相似文献   

Monitoring ambient ozone with a passive measurement technique method,field results and strategy     

Bert A. Scheeren  Eduard H. Adema 《Water, air, and soil pollution》1996,91(3-4):335-350

A low-cost, accurate and sensitive passive measurement method for ozone has been developed and tested. The method is based on the reaction of ozone with indigo carmine which results in colourless reaction products which are detected spectrophotometrically after exposure. Coated glass filters are mounted in a short polystyrene badge-type vessel in which the diffusion path is restricted by a Teflon membrane filter. From wind tunnel experiments good concentration-independent linearity has been found. The detection limit of the method is about 23 ppbv for 1 hour exposure. Tests with interfering oxidants, such as peroxyacetyl nitrate and NO₂, indicated no significant effects for common ambient conditions. No humidity effect was found when the relative humidity varied from 20 to 80%. The uptake rate of the sampler is dependent on wind velocity. In general an average air velocity of approximately 0.5 m/s is necessary to ensure a stable collection rate of ozone. This implies the necessity to measure wind speed during exposure or to place the samplers in the wind stream of a small fan. The method is suitable for hourly to daily mean measurements of ambient ozone. Under field conditions an accuracy of 11 ± 9% (40 experiments) was established in comparison to a continuous UV photometric monitor.  相似文献   

Plasma iron concentrations and systemic inflammatory response syndrome in neonatal foals     

Júlia Sanmartí  Lara Armengou  Judit Viu  Eduardo Alguacil  Sandra Civit  José Ríos  Eduard Jose-Cunilleras 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(3):1325-1331

  相似文献   

Observation of giant diffusivity along dislocation cores     

Legros M  Dehm G  Arzt E  Balk TJ 《Science (New York, N.Y.)》2008,319(5870):1646-1649

Diffusion of atoms in a crystalline lattice is a thermally activated process that can be strongly accelerated by defects such as grain boundaries or dislocations. When carried by dislocations, this elemental mechanism is known as "pipe diffusion." Pipe diffusion has been used to explain abnormal diffusion, Cottrell atmospheres, and dislocation-precipitate interactions during creep, although this rests more on conjecture than on direct demonstration. The motion of dislocations between silicon nanoprecipitates in an aluminum thin film was recently observed and controlled via in situ transmission electron microscopy. We observed the pipe diffusion phenomenon and measured the diffusivity along a single dislocation line. It is found that dislocations accelerate the diffusion of impurities by almost three orders of magnitude as compared with bulk diffusion.  相似文献   

Foraging Behavior of Alberes Cattle in a Mediterranean Forest Ecosystem     

Jordi Bartolomé  Josefina Plaixats  Jesús Piedrafita  Marta Fina  Eduard Adrobau  Aida Aixàs  Marina Bonet  Jordi Grau  Lluis Polo 《Strength and Conditioning Journal》2011,64(3):319-324

The dietary composition of the semiferal cattle population in the Alberes Natural Park in northeastern Spain was determined four times per year, from June 2002 to February 2004, by microhistological analysis of a total of 120 fecal samples. Woody species, mainly the Quercus and Erica genera, formed the bulk of the diet, reaching 89% of it in winter. However, in spring and summer, the proportion of woody and herbaceous species varied between samples, depending on the habitat where they were collected. The forest samples contained 67% woody species in summer, whereas grassland samples only contained 44%. The results showed that the Alberes cattle population grazed actively in Mediterranean forests and consumed a high proportion of the most combustible species, such as the Erica genus (39% of the epidermal fragments in winter samples). Even when grassland habitat was utilized, in spring and summer, one-third of the diet was from woody species. Some bovines, such as the Alberes cattle breed, can therefore survive year-round in a forest habitat with little forage supplementation, and the consumption of a predominantly woody diet would be expected to reduce forest fire hazards.  相似文献