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11.
Meritxell Aulinas Maite Garcia-Valles Domingo Gimeno Jose Luis Fernandez-Turiel Flavia Ruggieri Montserrat Pugès 《Environmental science and pollution research international》2009,16(4):443-452
Background, aim, and scope The first step in the restoration of a medieval stained glass window is the evaluation of its degree of degradation. This
implies the study of the chemical composition of the stained glass as well as the new mineral phases developed on its surface
(patinas). Patinas are clearly related to glass composition, time, environmental conditions, microenvironments developed in
local zones, bioactivity, physical and chemical factors, etc. This study was carried out on patinas developed in selected
Na-rich stained glass of the Santa Maria de Pedralbes Monastery (Barcelona, Spain). The location of this monument in the city
(about 5 km from the shoreline and close to the Collserola hill flank) helped to determine the environmental conditions in
which patinas developed. The aim of our study was to characterize the patinas formed on the surface of the selected glass
of this monastery in order to understand the role of the chemical composition of the original glass (Na-rich) as well as the
environmental conditions in which they developed.
Materials and methods Powdered samples of two different color-type patinas (ochre-orange and brownish) were collected in the external and internal
parts of the stained glass windows of the Prebystery and Chapter House of the Pedralbes Monastery by using a precision (odontological)
drill. These patinas were subsequently analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).
Results XRD analyses evidenced the presence of sulfates (gypsum and thenardite), calcite, Ca-oxalates (whewellite and weddellite),
and quartz forming part of the patinas. Although these mineral phases can be found in both color-type patinas, whewellite
and thenardite are more common in the ochre-orange patinas. The results obtained were validated by the FTIR measurements.
It has been observed, when thenardite is present, that gypsum occurs as traces. Thenardite is in most of the cases associated
with whewellite and mainly occurs in the internal parts of the glass. In contrast, weddellite is limited to the absence of
thenardite and whewellite and to the external parts of the stained glass. Quartz is present in all the patinas independent
of their location and color. Calcite also occurs in many samples. It appears in both color-type patinas and, in some cases,
is associated to the presence of weddellite but not to whewellite and/or thenardite.
Discussion Glass composition together with environmental conditions and location of the patinas (internal or external parts of the stained
glass window), as well as the provenance of the glass within the monastery, are the main factors that define the development
of the new mineral phases. Moreover, the action of microorganisms, when present, can also strongly influence the development
of some mineral phases. For example, the formation of calcite in the external parts of the stained glass (associated with
the presence of oxalates) is related to the action of microorganisms. When calcite is formed in the internal parts of the
glass and it is not associated with the presence of Ca-oxalates, an inorganic origin can be invoked. The presence of weddellite
requires a very humid microenvironment with very little exposure to sunlight. In fact, this mineral phase has only been observed
in the external parts of some glass located in the humid and shady side of the monastery. Whewellite (which only appears in
the internal parts) needs a low degree of relative humidity. It has been observed that sulfur precipitating in basically one
mineral phase (thenardite or gypsum) depends on the microenvironmental conditions of the moment and the glass composition.
When thenardite occurs, it can be maintained that the original glass is of Na composition. The occurrence of quartz in all
samples is interpreted as being due to the deposition of atmospheric particulate matter. The color of the patinas can be originated
by different processes (presence of carotenes, organic pigmentation, atmospheric contamination, etc.).
Conclusions In the case of moderately weathered stained glass windows, the combination of XRD and FTIR techniques is very useful to obtain
a fast preliminary evaluation of the degree of weathering of a stained glass window. The presence of specific mineral phases
in the patina (e.g., thenardite) confirms the Na composition of the original stained glass. This is important since Na-rich
glass underwent a lesser degree of weathering than K- or K-Ca-rich glass. However, their absence cannot preclude other possibilities.
It has been extensively evidenced through time that environmental conditions play an important role on the formation of the
different mineral phases which form part of the patinas.
Recommendations and perspectives The first step in the restoration of a stained glass window is the evaluation of the degree of deterioration of the glass.
This evaluation includes a chemical analysis of the glass as well as a characterization of the patinas developed on their
surfaces. The obtained results will be essential in order to define the best restoration practices to be followed. 相似文献
12.
Among the diverse patterns of energy allocation to the offspring of gastropods, the presence of egg capsules to protect embryos
is common. Females of the edible snail Zidona
dufresnei attach egg capsules to hard substrates in shallow Argentine Patagonian waters (40°45′S, 64°56′W) during spring-summer. Embryonic
development takes about 30 days at 22°C. In this study, three likely capsule predator species and the marks left by each on
egg capsule walls were identified in laboratory experiments in February 2010. Abundances of predators and egg capsules with
evidence of predation were assessed in the field in the summers of 2010 and 2011. Under laboratory conditions (N = 10 replicates per treatment and control), the predation rate by the chiton Chaetopleura
isabellei was the highest (up to 90%), followed by the gastropod Tegula
patagonica and the crab Neohelice
granulata (~20% each). Nearly 60% of 41 capsules found in the field showed signs of predation. According to the marks identified in
the laboratory, C. isabellei was responsible for 79% of this predation, and T. patagonica for the rest. Predation appears to be important during the encapsulated early life and could be an agent for selecting for
resistant capsule walls and a relatively shorter development time. 相似文献
13.
Pedro Daleo Juan Alberti Maria Soledad Avaca Maite Narvarte Paulina Martinetto Oscar Iribarne 《Marine Biology》2012,159(10):2359-2365
Feeding decisions under predation risk can be a key in the life of scavenger organisms, and tuned recognition of predation alarm cues and flexibility in the response are fundamental. The effect of injured conspecifics on the response behavior of the whelk Buccinanops globulosum to feeding opportunities was experimentally evaluated in a Patagonian Bay (40°45′S, 64°56′W, Argentina) in September 2010. The effect of sex, size, body condition, or starvation on anti-predatory behavior was assessed. The number of B. globulosum feeding on carrion was reduced by half when damaged conspecifics were present. Smaller, lighter, and starved individuals responded less to the presence of damaged conspecifics. These results indicate that, under natural conditions, feeding avoidance after detecting damaged conspecifics is a common and important anti-predatory strategy of B. globulosum and show that morphology and starvation are significant factors in the context of the trade-off between feeding and avoiding predation risk. 相似文献
14.
Joan Navarro Maite Louzao José Manuel Igual Daniel Oro Antonio Delgado José Manuel Arcos Meritxell Genovart Keith A. Hobson Manuela G. Forero 《Marine Biology》2009,156(12):2571-2578
Pelagic seabirds obtain food from oceans where the availability of their prey changes rapidly both seasonally and spatially.
Here, we investigated changes in the trophic habits of the critically endangered Balearic shearwater (Puffinus mauretanicus) through the breeding season and tested for dietary differences between sexes and age classes. We analysed δ15N and δ13C values in blood of adults during the pre-incubation, incubation and chick-rearing periods and of their chicks. Using a two-isotope
mixing model, we estimated dietary contributions based on isotope values from potential prey species which included small
pelagic species available naturally and demersal fish species available only from trawling discards. Balearic shearwaters
showed clear isotopic and dietary variation through the breeding season. During pre-incubation, breeding adults appeared to
exploit demersal fish, whereas during the incubation and chick-rearing period, they fed mainly on pelagic anchovies (Engraulis encrasicolus) and pilchards (Sardina pilchardus). Similarly, chicks were fed mainly with anchovies, a resource with a high energetic value. This variation in the dietary
habits of adult shearwaters during the breeding season was probably related to both natural and fishery-induced seasonal changes
in the availability of potential prey species within their main feeding grounds. However, changes in the nutritional requirements
of the shearwaters could also play an important role. Indeed, diet differed between sexes during pre-incubation: females fed
less on trawling discards and more on small pelagic fish than males. This sexual segregation in diet could be the consequence
of higher nutritional requirements of females during this period. Our study reveals the differential importance of both trawling
discards and small pelagic fish species for a pelagic seabird depending on the breeding period and illustrates the importance
of considering the entire breeding season when making inferences about the importance of specific prey in seabird dietary
studies. 相似文献
15.
The effect of an oxidative pre-treatment with ozone on the removal of Pharmaceutical and Personal Care Products (PPCPs) during the anaerobic digestion of sewage sludge has been investigated. Besides, the digested sludge characteristics in terms of pathogens content, dewatering properties, heavy metals content and linear alkylbenzene sulfonates (LAS) were determined. During ozonation (20mg O(3)/g TSS), about 8% of volatile solids (VS) and 60% of the chemical oxygen demand (COD) were solubilized. However, no mineralization was observed. The elimination of VS and total COD during anaerobic digestion were not affected by ozone treatment with efficiencies ranging from 60% to 65%. All PPCPs considered were removed during anaerobic treatment of sludge, with efficiencies ranging from 20% to 99%. No significant influence of ozone pre-treatment was observed on PPCPs elimination except for carbamazepine. Pathogens, heavy metals and LAS contents after conventional and pre-ozonation treatment of sewage sludge were below the legal requirements. However, the dewatering properties of sludge were deteriorated when the ozone pre-treatment was applied. 相似文献
16.
Christine Lors Jean-François Ponge Maite Martínez Aldaya 《Environmental pollution (Barking, Essex : 1987)》2010,158(8):2640-2647
Five bioassays (inhibition of lettuce germination and growth, earthworm mortality, inhibition of springtail population growth, avoidance by springtails) were compared, using four coke factory soils contaminated by PAHs and trace elements, before and after biotreatment. For each bioassay, several endpoints were combined in an ‘ecoscore’, a measure of test sensitivity. Ecoscores pooled over all tested bioassays revealed that most organisms were highly sensitive to the concentration of 3-ring PAHs. When four soils were combined, behavioural tests using the springtail Folsomia candida showed higher ecoscores, i.e. they were most sensitive to soil contamination. However, despite overall higher sensitivity of behavioural tests, which could be used for cheap and rapid assessment of soil toxicity, especially at low levels of contamination, some test endpoints were more sensitive than others, and this may differ from a soil to another, pointing to the need for a battery of bioassays when more itemized results are expected. 相似文献
17.
Lors C Ponge JF Martínez Aldaya M Damidot D 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2974-2981
Bioassays on aqueous and solid phases of contaminated soils were compared, belonging to a wide array of trophic and response levels and using ecoscores for evaluating ecotoxicological and genotoxicological endpoints. The method was applied to four coke factory soils contaminated mainly with PAHs, but also to a lesser extent by heavy metals and cyanides. Aquatic bioassays do not differ from terrestrial bioassays when scaling soils according to toxicity but they are complementary from the viewpoint of ecological relevance. Both aquatic and terrestrial endpoints are strongly correlated with concentrations of 3-ring PAHs. This evaluation procedure allows us to propose a cost-effective battery which embraces a wide array of test organisms and response levels: it includes two rapid bioassays (Microtox(?) and springtail avoidance), a micronucleus test and three bioassays of a longer duration (algal growth, lettuce germination and springtail reproduction). This battery can be recommended for a cost-effective assessment of polluted/remediated soils. 相似文献
18.
Lorena P. Storero Matías Ocampo-Reinaldo Raúl A. González Maite A. Narvarte 《Marine Biology》2010,157(3):555-564
Phenotypic plasticity in response to environmental variability is one of the main characteristics of cephalopods. This study compares growth and life span of Octopus tehuelchus in different coastal environments of San Matías Gulf (Patagonia) at three different periods. The progression of maturity jointly with modal progression analysis and the detection of hatchlings in the natural environment were used to differentiate cohorts and assign ages. Growth was described using the oscillatory von Bertalanffy growth model. Within San Antonio Bay, O. tehuelchus seems to have the most favourable conditions for an extended spawning season and the development of two sub-annual cohorts. O. tehuelchus growth is strongly seasonal with slow growth rates during winter. There were differences in the growth pattern between sites and particularly between sub-annual cohorts in San Antonio Bay. The growth pattern in each site seems to be similar along the last 26 years. The results of our study make evident the variability and plasticity of O. tehuelchus in response to the environment. 相似文献
19.
Toribio-Avedillo Daniel Méndez Javier Muniesa Maite Blanch Anicet R. 《Food and environmental virology》2020,12(2):148-157
Food and Environmental Virology - Enteric bacteriophages (somatic coliphages, F-specific coliphages or both together) are now recognized as useful viral indicators in water, shellfish, and... 相似文献
20.
Odalys Quevedo Alvarez Margarita Edelia Villanueva Tagle Jorge L. Gómez Pascual Ma. Teresa Larrea Marín Ana Catalina Nuñez Clemente Miriam Odette Cora Medina Raiza Rey Palau Mario Simeón Pomares Alfonso 《Environmental monitoring and assessment》2014,186(10):6867-6878
Spatial and temporal variations of sediment quality in Matanzas Bay (Cuba) were studied by determining a total of 12 variables (Zn, Cu, Pb, As, Ni, Co, Al, Fe, Mn, V, CO3 2?, and total hydrocarbons (THC). Surface sediments were collected, annually, at eight stations during 2005–2008. Multivariate statistical techniques, such as principal component (PCA), cluster (CA), and lineal discriminant (LDA) analyses were applied for identification of the most significant variables influencing the environmental quality of sediments. Heavy metals (Zn, Cu, Pb, V, and As) and THC were the most significant species contributing to sediment quality variations during the sampling period. Concentrations of V and As were determined in sediments of this ecosystem for the first time. The variation of sediment environmental quality with the sampling period and the differentiation of samples in three groups along the bay were obtained. The usefulness of the multivariate statistical techniques employed for the environmental interpretation of a limited dataset was confirmed. 相似文献