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The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.  相似文献   
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Objective: To determine whether the standard Spanish driving test (ASDE test) was able to identify patients with Parkinson's disease (PD) at risk of unsafe driving and to examine the relationship between the ASDE test and the Useful Field of View (UFOV) as well as with a battery of neuropsychological tests in drivers with PD.

Methods: Thirty-seven patients with PD and 33 controls matched by age and education level were included in an observational study. All participants were active drivers and patients with PD underwent study procedures after taking the medication in the “on” period. Subjects with a Mini-Mental State Examination (MMSE) score ≤ 24 were excluded. Neuropsychological tests (Repeatable Battery for Neuropsychological Status [RBANS], Trail Making Test [TMT-A and -B], and Block Design test), driving performance tests (ASDE Driver Test and UFOV), and daytime sleepiness (Epworth Sleepiness Scale) were assessed.

Results: The PD group performed significantly worse than healthy controls in the ASDE Motor Coordination tests. No significant differences were observed in anticipation speed, multiple reaction time, concentrated attention, and resistance to monotony. All participants successfully completed the UFOV tests. Statistically significant differences between patients with PD and controls were found in processing speed (UFOV1; P =.03) and more patients with PD were found in the categories of higher driving risk levels (P =.03). In addition, patients with PD showed worse scores than healthy controls in visuospatial capacities (Line Orientation), psychomotor speed (Coding and TMT-A), memory (List Recognition, Story Recall), and executive function (TMT-B). The driving tests (ASDE and UFOV) showed a low sensitivity and a high specificity but a higher percentage of patients in the PD group failed in multiple reaction time, concentrated attention, and resistance to monotony. In addition, 18.9% of patients with PD showed a cutoff of 4 for UFOV risk. In the discriminant analysis, Line Orientation (visuospatial/constructive domain) and Figure Recall (delayed memory) were found to be statistically significant with a rate of correct classification of unsafe drivers with PD of 78.2%. In addition, normal results on the Line Orientation item were associated with a 1.5 times higher probability of non-risky driving in the multivariate analysis.

Conclusions: At early stages of the disease, about 19% of patients with PD showed difficulties that may affect their driving capabilities. Line Orientation and Figure Recall are useful to alert clinicians to the risk of unsafe driving. For this reason, patients with PD should be evaluated for driving abilities more regularly to determine the extent of deficits that may influence driving performance.  相似文献   

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The geochemistry of PM10 filter samples collected at sea during the Scholar Ship Atlantic–Mediterranean 2008 research cruise reveals a constantly changing compositional mix of pollutants into the marine atmosphere. Source apportionment modelling using Positive Matrix Factorization identifies North African desert dust, sea spray, secondary inorganic aerosols, metalliferous carbon, and V–Ni-bearing combustion particles as the main PM10 factors/sources. The least contaminated samples show an upper continental crust composition (UCC)-normalised geochemistry influenced by seawater chemistry, with marked depletions in Rb, Th and the lighter lanthanoid elements, whereas the arrival of desert dust intrusions imposes a more upper crustal signature enriched in “geological” elements such as Si, Al, Ti, Rb, Li and Sc. Superimposed on these natural background aerosol loadings are anthropogenic metal aerosols (e.g. Cu, Zn, Pb, V, and Mn) which allow identification of pollution sources such as fossil fuel combustion, biomass burning, metalliferous industries, and urban–industrial ports. A particularly sensitive tracer is La/Ce, which rises in response to contamination from coastal FCC oil refineries. The Scholar Ship database allows us to recognise seaborne pollution sourced from NW Africa, the Cape Verde and Canary islands, and European cities and industrial complexes, plumes which in extreme cases can produce a downwind deterioration in marine air quality comparable to that seen in many cities, and can persist hundreds of kilometres from land.  相似文献   
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IKONOS panchromatic images from a single year were used to characterise the effects of an extreme rainstorm event on six mountain catchment areas in Venezuela. Image registrations were accomplished using topographic base maps at 1 : 5000 scale giving a mapping accuracy between 37 and 40 m. It was used an 8-bit channel for correction, rectification, filteration and tone enhancements.Landsliding was discerned in the affected watersheds using morphometric criteria, including the shape of the slope failure and its position, exposure bedrock in the scar and deposition of debris down-slope. This study is restricted to the impact analysis of the distribution of landslide erosion scars and the depositional processes on the valley floor. Remote sensing data were combined into a geographic information system (GIS) with planimetric data, contour lines, hydrology and vegetation types to evaluate the distribution of the scars and their effects on the highly populated areas located on the alluvial fans. Hillslope mass wasting induced mass movements, logging and increased the mud and silt in floodwaters affecting settlement down-slope.  相似文献   
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Collection of standardized assessment and monitoring data is critically important for supporting policy and management at local to continental scales. Remote sensing techniques, including image interpretation, have shown promise for collecting plant community composition and ground cover data efficiently. More work needs to be done, however, evaluating whether these techniques are sufficiently feasible, cost-effective, and repeatable to be applied in large programs. The goal of this study was to design and test an image-interpretation approach for collecting plant community composition and ground cover data appropriate for local and continental-scale assessment and monitoring of grassland, shrubland, savanna, and pasture ecosystems. We developed a geographic information system image-interpretation tool that uses points classified by experts to calibrate observers, including point-by-point training and quantitative quality control limits. To test this approach, field data and high-resolution imagery (∼3 cm ground sampling distance) were collected concurrently at 54 plots located around the USA. Seven observers with little prior experience used the system to classify 300 points in each plot into ten cover types (grass, shrub, soil, etc.). Good agreement among observers was achieved, with little detectable bias and low variability among observers (coefficient of variation in most plots <0.5). There was a predictable relationship between field and image-interpreter data (R 2 > 0.9), suggesting regression-based adjustments can be used to relate image and field data. This approach could extend the utility of expensive-to-collect field data by allowing it to serve as a validation data source for data collected via image interpretation.  相似文献   
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Lariophagus distinguendus (Hymenoptera: Pteromalidae) is a generalist solitary ectoparasitoid parasitising immature stages of at least 11 foodstuff beetles from five families, including species developing in seeds of Poaceae and Fabaceae. In this study, we tested the role of visual and olfactory stimuli affecting L. distinguendus host location in the trophic context of Stegobium paniceum (Coleoptera: Anobiidae) infesting chickpeas, Cicer arietinum (Fabales: Fabaceae). When either visual plus olfactory cues or olfactory cues alone were provided, S. paniceum-infested chickpeas were more attractive than uninfested chickpeas to naïve L. distinguendus females. Larval faeces of S. paniceum also evoked strong attraction to female wasps. Uninfested chickpeas covered with host faeces were preferred over uninfested ones without faeces, while infested chickpeas were as attractive as healthy chickpeas plus host faeces. Overall, results demonstrated that L. distinguendus females orient their host-seeking decisions mainly on the basis of faeces-borne olfactory stimuli. Further research is on-going to characterise the volatiles from S. paniceum larval faeces to evaluate their attractiveness towards L. distinguendus females.  相似文献   
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