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Catechins, compounds that belong to the flavonoid class, are potentially beneficial to human health. To enable epidemiological evaluation of these compounds, data on their contents in foods are required. HPLC with UV and fluorescence detection was used to determine the levels of (+)-catechin, (-)-epicatechin, (+)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg) in 24 types of fruits, 27 types of vegetables and legumes, some staple foods, and processed foods commonly consumed in The Netherlands. Most fruits, chocolate, and some legumes contained catechins. Levels varied to a large extent: from 4.5 mg/kg in kiwi fruit to 610 mg/kg in black chocolate. (+)-Catechin and (-)-epicatechin were the predominant catechins; GC, EGC, and ECg were detected in some foods, but none of the foods contained EGCg. The data reported here provide a base for the epidemiological evaluation of the effect of catechins on the risk for chronic diseases.  相似文献   

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Catechins, compounds that belong to the flavonoid class, are potentially beneficial to human health. To enable an epidemiological evaluation of catechins, data on their contents in foods are required. HPLC with UV and fluorescence detection was used to determine the levels of (+)-catechin, (-)-epicatechin, (+)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg) in 8 types of black tea, 18 types of red and white wines, apple juice, grape juice, iced tea, beer, chocolate milk, and coffee. Tea infusions contained high levels of catechins (102-418 mg of total catechins/L), and tea was the only beverage that contained GC, EGC, ECg, and EGCg in addition to (+)-catechin and (-)-epicatechin. Catechin concentrations were still substantial in red wine (27-96 mg/L), but low to negligible amounts were found in white wine, commercially available fruit juices, iced tea, and chocolate milk. Catechins were absent from beer and coffee. The data reported here provide a base for the epidemiological evaluation of the effect of catechins on the risk for chronic diseases.  相似文献   

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Detailed soil mapping in the Ransdalerveld area pointed to the occurrence of clay soils of different ages, characteristics and genesis. Three representative soil profiles were therefore selected and studied in detail.In this first of three articles, some observations and conclusions on the distribution, age and characteristics of these soils are presented. The “old” soils, developed on the plateaus in predominantly limestone-weathering residues, are classified as Lithic Hapludalfs, whereas the “young” soils on the valley slopes are classified as Rendollic Eutrochrepts if they lack a loess cover and as Typic Hapludalfs if they have a loess cover. Weathering and soil formation are discussed in the second and third parts.  相似文献   

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The emission of acidifying compounds to air in the Netherlands, expressed as acidifying equivalents, consisted in 1992 mainly of NOX (45%), NH3 (35%) and SO2 (20%). Transportation, agriculture and large combustion plants each contributed about 30% to the national total emission of acidifying compounds. The emissions from transportation activities mainly consisted of NOX, while in agriculture NH3 emission strongly dominated. Combustion processes in large combustion plants resulted both in SO2 emissions (especially from refineries) and NOX emissions (especially from public power plants). The total emission of acidifying substances decreases steadily in the Netherlands. The emission in 1992 was 24% lower than in 1985. It is expected to decrease further in future. The emission levels in 1992 and 1993 still are more than twice as high as the emission objective for the year 2000, set by Dutch environmental policy.  相似文献   

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通过对2006-2010年河北理工大学收录论文的分析,可掌握学校的科研综合实力和科研工作中的不足,从而建立健全校内的学术评价制度。  相似文献   

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Nutrient management regulations in The Netherlands   总被引:2,自引:0,他引:2  
J.J. Schrder  J.J. Neeteson 《Geoderma》2008,144(3-4):418-425
The application of nutrients affect the quality of the environment which justifies the consideration of regulations regarding their use in agriculture. In the early 1990s The Netherlands decided to use the indicator ‘nutrient surplus at farm level’ as the basis for a regulation which was called the mineral accounting system (MINAS). Exceedance of specified nitrogen (N) and phosphorus (P) surpluses (‘N and P loss standards’), resulted in a financial levy per kg exceedance. This NP surplus approach is a ‘goal-oriented regulation’ rather than a ‘means-oriented regulation’, giving farmers maximum freedom to stop nutrient leaks where they considered measures to be most effective in their specific situation. In 2003, however, the European Court of Justice ruled that The Netherlands Action Programme, of which MINAS was part, was in conflict with the EU Nitrates Directive. Important consideration here was that the legislation in The Netherlands contained as yet no specified application rates for N. The Netherlands was also reproached for implicitly allowing application rates of more than 170 kg N in the form of animal manure per ha per year without possessing formal permission by the European Commission to deviate from this threshold, a so-called ‘derogation’. A new, and meanwhile by the European Commission accepted Netherlands Action Programme defines the required N application rates, N fertilizer replacement values of various organic manure types, and periods in which the use of fertilizers and manures is forbidden. All these aspects will be sharpened in the years after 2006.  相似文献   

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The objective of this study was to estimate the societal economic burden associated with work-related ATV fatalities among civilian persons more than 17 years of age in the U.S. from 2003 through 2006. ATV death data were obtained from the Bureau of Labor Statistics' annual Census of Fatal Occupational Injuries. Costs were estimated using a model employing a cost-of-illness method developed by the National Institute for Occupational Safety and Health. From 2003 to 2006, a total of 129 work-related ATV deaths occurred among persons more than 17 years of age in the U.S., nearly doubling from 20 deaths in 2003 to 39 deaths in 2006. The collective lifetime cost of the deaths was $103.6 million (M), with a four-year mean of $803,100 and a four-year median of $772,100. Decedents age 35 to 54 years accounted for one-third of the deaths (n = 41) at a cost of $50.1 M. Montana had the most deaths (13). Fifty-two percent of the deaths were overturns costing $48.3 M. Eighty-four (65%) of the deaths were workers in agricultural production at a cost of $62.3 M. Short-term investment in prevention measures, such as training and helmets for workers, could provide lasting dividends by preventing work-related ATV deaths and reducing their economic impact.  相似文献   

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This paper describes the application of the EROSION 3D soil erosion model to the CATSOP catchment in the Netherlands using data of 10 storms from the period of 1987 to 1993. Based on observed runoff data the model was calibrated by adjusting initial soil moisture. The computations result in a raster map showing the spatial pattern of predicted erosion and deposition within the catchment. The map corresponds qualitively well with reality. For a quantitative evaluation, the model results were compared with observed sediment data measured at the channel when it leaves the catchment. The comparison shows that simulated soil loss was generally too high. This discrepancy might be caused by weak input data and the presence of processes—such as erosion and deposition within the channel—which are not covered by the model.  相似文献   

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Due to seasonal variation in bottom-water temperature and degradation of organic matter, the depths of the redox boundaries fluctuate in sediments of the river Meuse. This is reflected by a non-steady state behaviour of heavy metals in the surface sediments. Levels of acid-volatile sulphides suggest that dissolved concentrations of heavy metals in the anoxic pore waters are determined by their respective sulphide phases. However, complexation with dissolved organic ligands may significantly increase dissolved concentrations of heavy metals. In most sediments studied, a distinct peak in dissolved concentrations of heavy metals is measured immediately below the sediment-water interface. This concentration peak may be attributed to degradation of organic matter and oxidation of sulphides. Dissolved concentration gradients indicate that upward diffusion of heavy metals from the sediment can contribute to concentrations in the surface water, although significant effects may be confined to specific locations. In addition, it is shown that release of heavy metals as dissolved species to the surface water is negligible compared to particulate-bound fluxes of heavy metals to the sediment.  相似文献   

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《Geoderma》2006,130(3-4):387-388
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