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351.
介绍了利用胶片生产中含铝废渣生产高效净水剂聚合氯化铝的工艺技术路线。结果表明 ,该产品技术指标符合国家标准 ,且生产过程具有工艺简单、投资少 ,不产生二次污染等特点。  相似文献   
352.
姜震  王德忠  陆贻通 《上海环境科学》2003,22(12):935-938,942
采用同位素示踪方法,以3个不同抗蚜威剂量对青菜进行喷施,研究其在青菜-土壤系统中的残留动态。试验显示,在不同浓度处理下,抗蚜威在青菜中的消解规律大致为前期较快,后期较慢:浓度高时较快,浓度低时较慢。常规剂量处理的试验末期,土壤中结合残留物占初始量的比例高达60.75%左右。抗蚜威在青菜-土壤系统中的残留动态变化,能较好的用指数模型和示踪动力学二分室模型描述。  相似文献   
353.
土壤中农药残留的现状及其治理   总被引:1,自引:0,他引:1  
综述了农药在土壤中的残留现状及其影响因素,总结了综合治理土壤中农药残留的对策.  相似文献   
354.
The intent of this article is to outline, integrate, and interpret relevant scientific, economic, and social issues of rbST technology that have contributed to the acceptance dilemma for this product. The public is divided into social groups, each with its own set of criteria on which they base rbSTs acceptability. Criteria for the scientific community may best be described as physiological. However, for consumers, criteria may be more practical, or procedural, including human health, animal welfare, environmental concerns, and overproduction. Because the business of dairy production depends on demand from the consuming public, the criteria for acceptance of rbST by producers largely reflects those of the consumers. Of necessity, producers are also critical of rbST from a business and animal improvement standpoint. Although this article demonstrates that rbST has met most physiological criteria for acceptance, the consuming public has treated the acceptance issue with forceful skepticism. The question this article addresses is, why? The authors comment that with rbST and other biotechnologies applied to agricultural animal production, it will be the responsibility of government health agencies, scientists, and manufacturers of the products to provide early, adequate, and honest public education. Attention to the concerns of the public may be the only means to prevent hysteria over this and future agricultural products of biotechnology and will, therefore, allow the public to form logical and thoughtful criteria assessments with respect to acceptance or rejection of each product.  相似文献   
355.
Fenamidone is an imidazolinone fungicide recently introduced in viticulture practices. This work reports the validation and assessment of global uncertainty of a gas chromatographic with mass spectrometry method to analyze fenamidone in grapes and wines. This method consists in a simple and fast liquid-liquid extraction step followed by chromatographic determination. Limits of detection for fenamidone in grapes and wines were, respectively, 0.05 mg/kg and 0.06 mg/L, precision was below 9.4% and average recovery was 89 ± 5%. In the concentration range from 0.05 to 1.00 mg/kg (or mg/L) of fenamidone, global uncertainty calculated following the EURACHEM/CITAC rules, and also by the Horwitz function, was below 25%. The EURACHEM/CITAC global uncertainty budget used gave lower estimates than those obtained from the Horwitz function.  相似文献   
356.
Abstract

Residue disappearance and leaching of 14C‐allyl‐alcohol from different soils were studied in laboratory experiments. Additionally, the uptake of residues by lettuce and carrots was investigated in the greenhouse. In laboratory experiments, residue disappearance and leaching from soils was correlated negatively to the organic matter content. In greenhouse experiments with a sandy loam soil at an application rate normally used in practice, an average of 12.5 % of the applied radioactivity was recovered after an eight day interval between application and sowing. Furthermore, an average of 8 % (sum in soil and plants) of the applied radioactivity was recovered after lettuce or carrot growing. Uptake of residues was higher by carrots than by lettuce, and higher by lettuce roots than by lettuce tops. No bioaccumulation was observed. The residues in soils and plants were, to a high percentage, unextractable and, to a smaller extent, fully water‐soluble products. Unchanged allylalcohol could not be detected by the analytical methods used.  相似文献   
357.
甲磺隆结合残留对土壤酶活性的影响   总被引:3,自引:0,他引:3  
为了研究甲磺隆结合残留对土壤酶活性的影响,将黄粉土(水稻土)经甲磺隆结合残留处理98天,检测土壤脲酶、酸性磷酸酶、过氧化氢酶和蔗糖酶活性.结果表明,甲磺隆结合残留对土壤酶活性的影响不仅与甲磺隆结合残留处理浓度和培养时间有关,同时还与土壤酶种类有关.培养前期(第14天前),甲磺隆结合残留对土壤酸性磷酸酶和过氧化氢酶具有抑制作用,而对土壤脲酶和蔗糖酶的影响则表现为低浓度时激活,高浓度时抑制;培养后期(第14天后),甲磺隆结合残留对土壤脲酶、酸性磷酸酶和过氧化氢酶具有激活作用,在一定浓度范围内(0.050~0.281mg·kg-1)对土壤蔗糖酶也具有一定激活作用;就土壤酶而言,在污染早期,土壤过氧化氢酶对甲磺隆结合残留较敏感,可以作为表征甲磺隆结合残留土壤污染的生物活性指标.  相似文献   
358.
A field study was conducted to measure the dislodgeable residues of profenofos applied to jasmine (Jasminum sambac) and risk assessment was done for laborers engaged in picking of flower buds. Profenofos was applied at 0.10, 0.15, and 0.20% concentration and the jasmine bud samples were analysed for residues using GC. The initial deposit of 1.6–3.8, 3.8–7.1, and 5.2–7.6 µg cm?2 was detected on jasmine buds at 0.10, 0.15, and 0.20% concentration, respectively. At the recommended dose of 0.10%, the half-life was 1–2 days and the dislodgeable residues disappeared within 7 days. The results indicate faster disappearance of dislodgeable residues on jasmine buds. Risk assessment was done based on dislodgeable foliar residues and exposure estimates based on surrogate data and expressed as Margin of Exposure (MOE). The entry restrictions for exposure of jasmine flower pickers to profenofos, would be at least, 1 day following application, for the recommended concentration of 0.10% (MOE = 106) and 3 days, at higher concentrations of 0.15% (MOE = 156) and 0.20% (MOE = 115).  相似文献   
359.
Oxyfluorfen is a post-emergence herbicide used for control of annual and perennial broad-leaf weeds and sedges in rice. There is increasing concern about persistence of pesticide residues in soils, agricultural products and sub-sequent contamination of ground water through runoff, leaching and drift. Thus, persistence of oxyfluorfen was evaluated under field conditions in a rice cropping system. Oxyfluorfen was sprayed at 240 and 500 g ai ha?1 application rates to the rice crop as post-emergence herbicide. Paddy grains, straw and soil samples were collected at harvest and analyzed for oxyfluorfen residues by HPLC. Straw samples contained 0.01 and 0.03 µg g?1 oxyfluorfen residues at 240 and 500 g ha?1 concentrations, respectively. In the soil, 0.028 and 0.03 µg g?1 of oxyfluorfen residues were detected when applied at 240 and 500 g ai ha?1, respectively. However, in rice grains, 0.018 and 0.106 µg g?1 of oxyfluorfen residues were found in 240 and 500 g ai ha?1 treated plots. In light of the potential adverse effects of oxyfluorfen, it is important to determine herbicide levels in these crops.  相似文献   
360.
The average initial deposits of carbaryl were observed to be 1.4 and 3.1?mg?kg?1, respectively, following four applications of the insecticide at 4.95 and 9.9?kg active ingredient per hectare. Residues of carbaryl dissipated below its limit of quantification of 50?µg?kg?1 after 7 and 10 days at single and double the application dosage, respectively. The half-life values (t 1/2) of carbaryl were worked out to be 1.3 and 0.7 days, respectively, at single and double dosages. The acceptable daily intake (ADI) for carbaryl has been fixed at 8?µg?kg?1 body weight per day. Keeping in view the residues of carbaryl observed one day after the last application, a child of 10?kg and an adult of 60?kg will have an intake of 77 and 154?µg carbaryl after consumption of 100 and 200?g grapes, in comparison to its ADI of 80 and 480?µg; thus, no health risk is to be expected. Therefore, a waiting period of 1 day has been suggested for the safe consumption of carbaryl-treated grapes to avoid any health hazards.  相似文献   
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