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391.
To examine bioconcentration factors (BCFs) of mercury by Parasol Mushroom (Macrolepiota procera) roughly similarly sized (a cap diameter) fruiting bodies of this fungus and underlying soil (0–10 cm) samples were collected at 15 sites in Poland between 1995 and 2003. The total mercury content of the individual caps and stipes of Parasol Mushroom ranged from 0.05 to 22 mg Hg/kg dry matter (d.m.) and from 0.05 to 20 mg Hg/kg d.m., while the means were from 1.1 to 8.4 mg Hg/kg d.m. and from 0.83 to 6.8 mg Hg/kg d.m., respectively. The caps generally contained higher concentrations of mercury when compared to stipes, and the means of the cap to stipe mercury concentration quotient ranged from 1.3 to 4.6. The range of mercury concentration in topsoil samples collected at the sites where the fruiting bodies were collected was from 0.01 to 0.54 mg/g d.m. (means ranged from 0.022 to 0.36 mg/g d.m.). The BCFs factors for total mercury varied from 0.52 to 470 for individual caps and 0.52 to 360 for stipes, while average values, depending on the site, were from 16 to 220 and from 7.6 to 130 for caps and stipes, respectively.  相似文献   
392.
Jeremy Shoham 《Disasters》1987,11(4):282-285
A major area of investment in data collection in developing countries has been that of nutritional surveillance and monitoring. From recent debate it is clear that there is currently no consensus on the potential role of nutritional status as an early warning indicator. The author presents a synthesis of the broad spectrum of views on the role nutritional surveillance could or should have in early warning. Conceptual problems and technical difficulties are reviewed in the light of recent experiences in Africa and Asia. The author raises a number of issues for future discussion in this ongoing debate.  相似文献   
393.
Sally Dunbar 《Disasters》1984,8(3):174-177
In a long term Somali refugee camp where nutritional and general health status of children is now considered satisfactory and stable, a randomized community based survey of 300 children under five years was undertaken. Results indicate that the prevalence of protein-energy malnutrition is rising again: 17.3% of children are <80% median weight/height and 1.7% are <70%median weight/height. In addition, there is a high prevalence of anaemia: 50.5% have a haemoglobin level <9g% and 10.8%≤6g%. This cannot be explained by chronic malaria as the spleen rate is only 2%. Stool examination of 161 children show 29.8% to have evidence of Giardia Lamblia infection but this is not statistically correlated with either anaemia or with protein-energy malnutrition. Other potentially pathogenic parasites are uncommon and no hookworm is seen. Examination of blood films of anaemic children shows hypochromia as a striking feature.
It is concluded that nutritional deficiencies are a likely major factor in the aetiology of the anaemia. Both protein-energy malnutrition and anaemia seem related to the weaning period. Food rations for refugees, although adequate for short term needs, may be qualitatively deficient for long term subsistence, especially as regards young children.  相似文献   
394.
This paper reports the results obtained from the data collected within the European Commission funded project SAFEFOODNET regarding the state of the art in the control of chemical food contaminants in twelve European New Member States and one Associated Candidate Country (Turkey). Information has been gathered on institutions involved in food chemical contamination control, types of contaminants and matrices analyzed, procedures for data quality assurance, purposes of the analyses and accessibility of data in the participant countries. The resulting picture points out the general availability of adequate capabilities for the analysis of food contaminants in the laboratories in charge of control and the performance of the analysis of a large variety of chemicals (persistent organic pollutants, polycyclic aromatic hydrocarbons, pesticides, mycotoxins, heavy metals, radionuclides) in almost each country with few exceptions (dioxins in Bulgaria, Turkey, Latvia, persistent organic pollutants in Lithuania and Malta, polycyclic aromatic hydrocarbons in Malta). The application of validated analytical methods and the process of laboratory accreditation are partially fulfilled within the investigated countries, but still forthcoming for some countries, as in Romania, Turkey and Malta. Information collected on food controls is only partially available online and the language used is prevalently local and English to a lesser extent.  相似文献   
395.
食品废物含有大量的油脂,本研究对食品废物的油脂含量进行了连续监测,以其为原料开展生物柴油的制备研究,并对其组成进行测试分析,同其他原料所得生物柴油作对比,结果表明:食品废物的平均含油率均超过了10%(干基)。利用食品废物中提取的废弃油脂制取的生物柴油以棕榈酸甲酯、油酸甲酯和亚油酸甲酯含量最高,分别为38.70%、亚油酸甲酯18.32%和棕榈酸甲酯31.72%,其组成与以植物油为原料合成生物柴油组成基本相似,符合作为柴油替代品的要求。  相似文献   
396.
Food waste treatment plants(FWTPs) are usually associated with odorous nuisance and health risks, which are partially caused by volatile organic compound(VOC) emissions. This study investigated the VOC emissions from a selected full-scale FWTP in China. The feedstock used in this plant was mainly collected from local restaurants. For a year, the FWTP was closely monitored on specific days in each season. Four major indoor treatment units of the plant, including the storage room, sorting/crushing room, hydrothermal hydrolysis unit, and aerobic fermentation unit, were chosen as the monitoring locations.The highest mean concentration of total VOC emissions was observed in the aerobic fermentation unit at 21,748.2–31,283.3 μg/m3, followed by the hydrothermal hydrolysis unit at 10,798.1–23,144.4 μg/m3. The detected VOC families included biogenic compounds(oxygenated compounds, hydrocarbons, terpenes, and organosulfur compounds) and abiogenic compounds(aromatic hydrocarbons and halocarbons). Oxygenated compounds,particularly alcohols, were the most abundant compounds in all samples. With the use of odor index analysis and principal components analysis, the hydrothermal hydrolysis and aerobic fermentation units were clearly distinguished from the pre-treatment units, as characterized by their higher contributions to odorous nuisance. Methanthiol was the dominant odorant in the hydrothermal hydrolysis unit, whereas aldehyde was the dominant odorant in the aerobic fermentation unit. Terpenes, specifically limonene, had the highest level of propylene equivalent concentration during the monitoring periods. This concentration can contribute to the increase in the atmospheric reactivity and ozone formation potential in the surrounding air.  相似文献   
397.
广西沿江重镇洪灾特点及减灾对策   总被引:4,自引:0,他引:4  
曾令锋 《灾害学》1997,12(4):75-79
阐述了广西沿江重镇洪灾的主要特点:暴雨强度大、洪水灾发性强、抗灾能力低,探讨了致灾的成因;指出了防洪减灾的主要对策是强调工程与非工程防洪措施相结合,建立全流域综合防洪体系及根据各城市的具体情况采取针对性的措施。  相似文献   
398.
This paper examines the rate of degradation of food waste in a leach bed reactor (LBR) under four different operating conditions. The effects of leachate recirculation at a low and high flow rate are examined with and without connection to an upflow anaerobic sludge blanket (UASB). Two dilution rates of the effective volume of the leach bed reactors were investigated: 1 and 6 dilutions per LBR per day. The increase in dilution rate from 1 to 6 improved the destruction of volatile solids without connection to the UASB. However connection to the UASB greatly improved the destruction of volatile solids (by almost 60%) at the low recirculation rate of 1 dilution per day. The increase in volatile solids destruction with connection to the UASB was attributed to an increase in leachate pH and buffering capacity provided by recirculated effluent from the UASB to the leach beds. The destruction of volatile solids for both the low and high dilution rates was similar with connection to the UASB, giving 82% and 88% volatile solids destruction respectively. This suggests that the most efficient leaching condition is 1 dilution per day with connection to the UASB.  相似文献   
399.
为进一步提高学院食品质量与安全专业毕业生的就业质量,对2009-2011届毕业生共计147人进行了就业跟踪调查,从毕业生生源区域情况、毕业生就业率、就业情况三个方面进行分析,发现该专业毕业生以中小企业就业为主,结合专接本继续深造。为提高就业质量,围绕专业内涵建设提出几点建议。  相似文献   
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