排序方式： 共有38条查询结果，搜索用时 46 毫秒
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Farm tourism in Spain: a gender perspective 总被引：2，自引：0，他引：2
Alba Caballé 《GeoJournal》1999,48(3):245-252
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Francisca Arratia Pamela Olivares-Ferretti Alba García-Rodríguez Ricard Marcos 《新西兰海洋与淡水研究杂志》2019,53(3):460-469
Copper-based nanoparticles (NPs) are being widely used in different application fields and their health impacts to aquatic environments represent a current concern. Few studies are available about their comparative toxicity with their bulks and ions under natural exposition in aquatic organisms. Thus, the toxicity of Cu and CuO NPs and their microparticle and ionic forms was assayed in the acute immobilisation test of Daphnia magna by using freshwater media. Electronic microscopy, laser doppler velocimetry, and dynamic laser scattering methodologies were used to NPs characterisation. The results indicated that CuNPs and CuONPs were more toxic than their microparticles. Among NPs, CuNPs showed higher toxicity than CuONPs. Copper-based nanoparticles showed similar hydrodynamic particle size and were agglomerated in culture media, suggesting toxic-ionic release relationship and corroborated by the high toxicity induced by CuSO4. Additionally, water chemistry of natural freshwater used in the experiments also favoured the ion release of these NPs. 相似文献
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de la Vara Alba Cabos William Sein Dmitry V. Sidorenko Dmitry Koldunov Nikolay V. Koseki Shunya Soares Pedro M. M. Danilov Sergey 《Climate Dynamics》2020,54(11-12):4733-4757
Climate Dynamics - Despite the efforts of the modelling community to improve the representation of the sea surface temperature (SST) over the South Eastern Tropical Atlantic, warm biases still... 相似文献
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M. Scaioni L. Barazzetti A. Giussani M. Previtali F. Roncoroni M. I. Alba 《Earth Science Informatics》2014,7(2):83-95
This paper presents two innovative methods for tunnel monitoring that are based on digital photogrammetry. Both have been conceived to speed up operations that are currently accomplished by using engineering geodesy techniques and instruments. On the same time, proposed solutions are cheap and affordable. The first one is aimed at measuring relative deformations of transversal cross-section of tunnels. Some special targets are placed on the tunnel vault and their coordinates are measured by means of a small photogrammetric block made up of four images. A wire is used to setup the scale and to make all measurements comparable overtime. The second method can be applied for the measurement of vertical deformations along the longitudinal profile of tunnels. A new image-based approach called ‘photogrammetric levelling’ is discussed here, which is based on the metric rectification of each single image depicting a couple of special rods to be hung on levelling benchmarks. This technique can be used to replace traditional optical and digital level instruments. Both applications can be carried out by using a calibrated amateur camera. Some experiments in controlled and real environments allowed assessing performances and limitations of these techniques for operational surveys in tunnel monitoring. 相似文献
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M. D. Alba M. A. Castro P. Chain M. Naranjo A. C. Perdigón 《Physics and Chemistry of Minerals》2005,32(4):248-254
Syn-1, is a synthetic mica–montmorillonite interstratified mineral that forms one of the standard clay samples in the Clay Minerals Society Source Clays Project. However, there are still controversies regarding some structural aspects such as the interlayer composition or the location of the extra-aluminium determined by chemical analysis. The main objective of this paper is to shed light on those structural aspects that affect the reactivity of the interstratified minerals. For this purpose, we have used 1 H–29 Si and 1 H–27Al HETCOR MAS NMR to show that it is likely that the interlayer space of the beidellite part is composed of ammonium ions whereas ammonium and aluminium ions are responsible for the charge balance in the mica type layer. 相似文献
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To accurately document the accelerated changes in biodiversity, scientists need an accurate historic baseline to which to compare the current state of a locale. These historic baselines are hard to come by, and specifically in the coastal principality of Asturias (northern Spain), biodiversity information before 1980 is scarce, fragmented, or entirely lacking. However, most families still keep old photographs, and we wondered if these historic documentations of the environment could provide missing baseline biodiversity data. We conducted a case study asking volunteers to find old family photographs, then return to the same place to retake the photograph from the same perspective. We compiled these photographs and analyzed the changes in biodiversity indices between the past and present. Thus, we quantified diversity changes in the region over the last century. 相似文献
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Francesco Crea Alba Giacalone Antonio Gianguzza Daniela Piazzese Silvio Sammartano 《Marine Chemistry》2006,99(1-4):93
In this paper SIT and Pitzer models are used for the first time to describe the interactions of natural and synthetic polyelectrolytes in natural waters. Measurements were made potentiometrically at 25 °C in single electrolyte media, such as Et4NI and NaCl (for fulvic acid 0.1 < I /mol L− 1 < 0.75), and in a multi-component medium simulating the composition of natural waters at a wide range of salinities (for fulvic and alginic acids: 5 < S < 45) with particular reference to sea water [Synthetic Sea Water for Equilibrium studies, SSWE]. In order to simplify calculations, SSWE was considered to be a “single salt” BA, with cation B and anion A representing all the major cations (Na+, K+, Mg2+, Ca2+) and anions (Cl−, SO42−) in natural sea water, respectively. The ion pair formation model was also applied to fulvate and alginate in artificial sea water by examining the interaction of polyanions with the single sea water cation. Results were compared with those obtained from previous speciation studies of synthetic polyelectrolytes (polyacrylic and polymethacrylic acids of different molecular weights). Results indicate that the SIT, Pitzer and Ion Pairing formation models used in studies of low molecular weight electrolytes may also be applied to polyelctrolytes with a few simple adjustments. 相似文献
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Naves Acacia Samper Javier Pisani Bruno Mon Alba Dafonte Jorge Montenegro Luis García-Tomillo Aitor 《Hydrogeology Journal》2021,29(8):2655-2669
Groundwater availability, management and protection are great challenges for the sustainability of groundwater resources in the scattered rural areas of the Atlantic regions of Europe where groundwater is the only option for water supply. This report presents a hydrogeological study of the coastal granitic area of Oia in northwestern Spain, which has unique geomorphological and hydrogeological features with steep slopes favoring the erosion of the weathered granite. The hydrogeological conceptual model of the study area includes: (1) the regolith layer, which is present only in the flat summit of the mountains; (2) the slope debris and the colluvial deposits, which are present in the intermediate and lowest parts of the hillside; (3) the marine terrace; and (4) the underlying fractured granite. Groundwater recharge from rainfall infiltration varies spatially due to variations in terrain slope, geology and land use. The mean annual recharge estimated with a hydrological water balance model ranges from 75 mm in the steepest zone to 135 mm in the lowest flat areas. Groundwater flows mostly through the regolith and the detrital formations, which have the largest hydraulic conductivities. Groundwater discharges in seepage areas, springs, along the main creeks and into the sea. The conceptual hydrogeological model has been implemented in a groundwater flow model, which later has been used to select the best pumping scenario. Model results show that the future water needs for domestic and tourist water supply can be safely provided with eight pumping wells with a maximum pumping rate of 700 m3/day.
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