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51.

Purpose

Improving land use assessment in life cycle assessment (LCA) is a priority. Recently, soil organic carbon (SOC) depletion has been proposed as a transformation and occupation midpoint indicator to estimate impacts on biotic production potential (BPP). SOC depletion is recommended by the European Union in the International Reference Life Cycle Data System (ILCD) Handbook as a land use indicator. There is a consensus method to calculate SOC depletion in LCA, and ILCD proposes a set of characterization factors (CFs), but these lack geographical discrimination.

Methods

Our method of calculation for midpoint CFs follows Brandão and Milà i Canals (Int J Life Cycle Assess 18:1243–1252, 2013). We operationalize the method using SOC stocks from the LUCASOIL database of field measurements in Europe. We use potential natural vegetation (PNV) as the reference situation. CFs were calculated on a cell basis for 23 countries in Europe and grouped in three spatial scales (an administrative classification, NUTS II, and two biophysical classifications, ecoregion and climate region) according to soil type and land cover following a consensus map of cover classes. To evaluate the method’s results, CFs were applied in a case study.

Results and discussion

SOC stocks of European soils were obtained according to land use and soil type classes (excluding non-European Union countries) for the three spatial scales. A database of European transformation and occupation CFs is also presented and analyzed. The aggregation of CFs at biophysical scales (ecoregion and climate region) is similar, but NUTS II aggregation of CFs is problematic. The application of the CFs in the case study revealed significant differences compared to the outcome of using CFs collected from other land use models.

Conclusions

This paper is the first operationalization using field measurements of an updated version of the ILCD-recommended model for land use impacts in LCA. We obtained CFs for SOC depletion in Europe that can be nested within CFs suggested by ILCD since our results possess better spatial resolution but are only for European Union countries. The case study application highlighted the need for inventories to improve the spatial resolution of the life cycle processes to match the detail of LCIA models.
  相似文献   
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F is (0.170) and F it (0.259) values indicated a number of heterozygotes present in the population under study lower than that necessary to reach the Hardy-Weinberg equilibrium. The genetic variability found among the traditional sweet cassava cultivars assessed was considered wide, and the groups that were most distant were mostly cultivars from Toledo and Maringá.  相似文献   
54.
Interphase specimens, aspects of physiological reorganization and divisional morphogenesis were investigated in a strain of a hypotrichous ciliate highly similar to Urostyla grandis Ehrenberg, 1830 (type species of Urostyla), collected from a mangrove area in the estuary of the Paraíba do Sul river (Rio de Janeiro, Brazil). The results revealed that albeit interphase specimens match with the known morphologic variability in U. grandis, morphogenetic processes have conspicuous differences. Parental adoral zone is entirely renewed during morphogenesis, and marginal cirri exhibit a unique combination of developmental modes, in which left marginal rows originate from multiple anlagen arising from innermost left marginal cirral row, whereas right marginal ciliature originates from individual within‐row anlagen. Based on such characteristics, a new subspecies, namely U. grandis wiackowskii subsp. nov. is proposed, and consequently, U. grandis grandis Ehrenberg, 1830 stat. nov. is established. Bayesian and maximum‐likelihood analyses of the 18S rDNA unambiguously placed U. grandis wiackowskii as adelphotaxon of a cluster formed by other U. grandis sequences. The implications of such findings to the systematics of Urostyla are discussed.  相似文献   
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A total of 1,816 eels were sampled in 1988, from seven sampling areas. Four areas were located in brackish water and the remaining three were located in freshwater reaches of the Tagus river basin. Eels were more abundant in the middle estuary and decreased both in the upstream and in the downstream directions, with a predominance of males in higher density areas. Smaller individuals preferred more peripheral areas, such as margins and upper reaches in the brackish water zone, and the tributaries of the freshwater habitats. It was assumed that this distribution pattern resulted from three main factors: (i) the dominance of larger specimens; (ii) the need to avoid predators and; (iii) the search for better trophic conditions. The condition of the individuals generally decreased toward the upper reaches, apparently due to a corresponding decrease in feeding intensity. The presence of the Belver dam in the main river, 158 km upstream from the sea, seemed to impose major alterations to the described patterns. The concentration of specimens below this impassable obstacle yielded a reduction in the proportion of females and a decrease in the condition and survival of the eels, contributing to a reduction in the spawning success of this population. Suggestions to diminish the effects of the dam, and to preserve the fishery are also presented.  相似文献   
57.
Mimicry can directly affect the evolutionary history of models, mimics, and signal receivers. Mimics often use multimodal signaling to deceive receivers. Jamie et al. showed that brood parasitic birds display multimodal signaling of mimetic traits triggered by sexual and filial imprinting on host species. These resulting adaptations can interact with premating isolation barriers to strengthen reproductive isolation and potentially drive sympatric speciation.  相似文献   
58.
In this study we tested the use of mucus from five species of Neotropical marine batoid elasmobranchs to extract genomic DNA for barcoding and phylogenetic analysis. The DNA from all individuals sampled was successfully amplified and sequenced for molecular barcode, allowing 99–100% accuracy to the species level. This method proved to provide reliable and good-quality DNA for barcoding and phylogenetic analysis of Neotropical elasmobranchs, through rapid handling and with low disturbance to animals.  相似文献   
59.
Congenital Neospora caninum infection was diagnosed in two Saanen goat kids from two distinct herds with a history of abortion and weak newborn goat kids in the Southern region of the State of Minas Gerais, Brazil. The first kid was weak at birth, had difficulty to rise and was unable to nurse. Gross lesions of porencephaly and hydrocephalus ex vacuo were seen. Multifocal necrosis, gliosis and non-supurative encephalitis were observed in the brain. Several parasitic cysts with a thick wall that reacted strongly only with polyclonal antiserum to Neospora caninum were seen in the cerebral cortex, brain stem and cerebellum. The second kid was born from a Neospora caninum seropositive mother that aborted in the last pregnancy. It was born without clinical signs. The diagnosis of neosporosis was based on antibody titer of 1:800 to N. caninum by indirect fluorescence antibody test obtained from blood collected before the goat kid ingested the colostrum and Neospora caninum DNA was detected by polymerase chain reaction and sequenced from placenta. This is the first report of neosporosis in goats in the southeast region of Brazil.  相似文献   
60.
Zanthoxylum tinguassuiba essential oil (ZtEO) contains α-bisabolol, a known antiglioma sesquiterpene, among other potentially active substances. Medical applications of this essential oil require advances in the design of distinctive carriers due to its low water solubility and easy degradation by heat, light, and oxygen. The aim of this work was to evaluate enhancement in oxidative stability and the ability to reduce glioblastoma cell viability of ZtEO loaded into liposomes. Multi- and unilamellar vesicles were prepared to carry ZtEO. By using thermal analysis, it was observed that thermal-oxidative stability of the liposomal ZtEO was enhanced, when compared to its free form. Liposomal ZtEO also presented significant apoptotic-inducing activity for glioma cells. These results show that liposomal systems carrying ZtEO may be a potential alternative for gliobastoma treatment.  相似文献   
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