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61.
以北京动物园的地表水为例,利用引进的海藻提取物EC lean生物工程技术对富营养化地表水进行处理试验研究。试验结果表明:应用此项技术有效降低了水体的浊度、COD和BOD5,水体脱氮降磷明显,藻类细胞密度下降,水体富营养化得到控制,减轻了“水华”藻类的危害。此技术在北京动物园富营养化水体的治理上表现出明显的应用效果。  相似文献   
62.
This research work consists on valorizing poultry waste by biotransformation into biofertilizers, associating this agro-industrial waste with algae (abundant natural resources) and molasses (a by-product of the sugar refining industry) ensuring a good contribution of nutritional chemical elements and obtaining a balanced formulation. A total of seven different formulations of the above three components, were examined in a simplex centroid design. A fungal inoculum of Aspergillus niger was used as a fermentation agent for better quality of biotransformation. The monitoring of this biotransformation is ensured during 15 days by following the evolution of physicochemical and microbiological parameters and, to understand the bioconversion of the simple compounds of the biofertilizer mixture such as short aliphatic chains, sugar, and amino acids into soluble mineral compounds, a Fourier transform infrared spectroscopy (FTIR) analysis was carried out before and after biotransformation. Finally, germination and fertilization tests were performed to evaluate the efficiency of the final product on a barley crop. The overall results of the present study showed that the mixture which contained 68.75% poultry waste, 12.5% molasses, and 18.75% algae presented the better microbiological and chemical safety criteria required for a good biofertilizer according to NF U44-551 standard.  相似文献   
63.
魏红  孙博成  杨小雨  李克斌 《环境科学》2017,38(6):2393-2399
实验以H_2O_2和KI作为分子碘(I2)的来源,研究比较了超声、紫外分别增强H_2O_2/KI降解磺胺甲基嘧啶(sulfamerazine,SMR)的效果、主要影响因素、分子碘的生成、主要活性物种和产物.结果表明,超声、紫外均能有效增强H_2O_2/KI对磺胺甲基嘧啶的降解,超声的增强效果明显;pH值对磺胺甲基嘧啶的去除率影响较大,pH为2.6~5.6,去除率随pH升高而降低;自由基抑制结果表明,碘自由基(I·和I-2·)是超声、紫外增强H_2O_2/KI降解磺胺甲基嘧啶的主要活性物质.HPLC/MS/MS分析检测到一碘代苯.  相似文献   
64.
Disinfection by-products(DBPs) are a complex mixture of compounds unintentionally formed as a result of disinfection processes used to treat drinking water. Effects of long-term exposure to DBPs are mostly unknown and were the subject of recent epidemiological studies. However,most bioanalytical methods focus on a select few DBPs. In this study, a new comprehensive bioanalytical method has been developed that can quantify mixtures of organic halogenated compounds, including DBPs, in human urine as total organic chlorine(TOCl), total organic bromine(TOBr), and total organic iodine(TOI). The optimized method consists of urine dilution, adsorption to activated carbon, pyrolysis of activated carbon, absorption of gases in an aqueous solution, and halide analysis with ion chromatography and inductively coupled plasma-mass spectrometry. Spike recoveries for TOCl, TOBr, and TOI measurements ranged between 78% and 99%. Average TOCl, TOBr, and TOI concentrations in five urine samples from volunteers who consumed tap water were 1850, 82, and 21.0 μg/L as X~-, respectively.Volunteers who consumed spring water(control) had TOCl, TOBr, and TOI average concentrations in urine of 1090, 88, and 10.3 μg/L as X~-, respectively. TOCl and TOI in the urine samples from tap water consumers were higher than the control. However, TOBr was slightly lower in tap water urine samples compared to mineral water urine samples, indicating other sources of environmental exposure other than drinking water. A larger sample population that consumes tap water from different cities and mineral water is needed to determine TOCl, TOBr, and TOI exposure from drinking water.  相似文献   
65.
用苋菜红体系催化光度法测定痕量碘   总被引:3,自引:0,他引:3  
提供了痕量碘新的催化光度法测定方法,避免了原方法使用的剧毒试剂。新方法以草酸钠为活化剂,以高碘酸钾氧化苋菜红的催化反应为基点。方法的检出限为8×10~(-10)g/mL,测定碘离子量的线性范围为2.5×10~(-9)~1.3×10~(-7)g/mL,大多数常见离子不干扰测定。  相似文献   
66.
环境中碘与动物体内碘代谢关系的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
环境中碘与动物体内碘代谢关系的研究张庆朝,孙存孝,杨景芝,曾勇庆,张万福,杨世钺,王慧(山东农业大学动物科技学院,泰安271018)关键词:碘,降水,饮用水,绵羊尿.碘是人类发现的第二个生物必需的微量元素,是甲状腺激素组成不可缺少的成分,它的生理功能...  相似文献   
67.
This study was carried out to determine the occurrence, prevalence and contributing factors to the incidence of goitre in Yewa north local government area of Ogun state, southwestern Nigeria. To achieve these objectives, soil, water, and cassava tubers were collected from four villages – Igbogila, Egua, Sawonjo and Imoto and from Lagos (about 250 m to the ocean) as a reference location, in order to determine their iodine concentrations. The results of the analyses indicated a soil mean iodine range of 2.1–5.8 μg g−1; a cassava mean iodine value of 2.3–3.5 μg g−1 and a drinking water mean iodine value of generally <1.0 μg L−1 in all the four villages. These values of iodine in soil and water of the four villages are considered low when compared with the soil iodine value of 7.4 μg g−1 and water iodine value of 6.1 μg L−1 obtained from Lagos. The limestone unit of the study area remains an inhibiting factor in the bioavailability of the iodine because of its alkalinity. Statistical analysis has shown that there was significant difference between iodine concentration in the soils and the drinking water, and a correlation between the soil iodine and organic matter content at p < 0.05. The correlation between soil iodine and granulometric fractions occurred at p < 0.01. Potential goitrogens in the commonly consumed cassava products might also have contributed to the prevalence of goitre in the study area. Both the females and the adults (i.e., less mobile groups) were found to be vulnerable to goitre development in these villages.  相似文献   
68.
The illusion of environmental iodine deficiency   总被引:2,自引:0,他引:2  
The distribution of endemic goitre in England and Wales was compared with the distribution of environmental iodine (atmospheric deposition, soil, surface water). Despite a very clear goitre belt through the west of England and Wales there was no patterning in the environmental iodine distribution. A clear seasonal variation in depositional iodine exists, with an unusually high concentration of iodine in March 1997. The temporal variation in iodine concentration is determined at the monthly and not the annual level. The presence of endemic goitre is no indicator of how iodine is distributed in the environment or vice versa!  相似文献   
69.
水处理活性炭吸附性能指标的表征与应用   总被引:11,自引:0,他引:11       下载免费PDF全文
使用碘值、苯酚值、甲基蓝值和丹宁酸值4种吸附容量性能指标组成水处理活性炭选型技术.经BET测试验证,碘值可以体现活性炭中孔径略大于1.0nm微孔的发达程度,表征比表面积大小;甲基蓝值则代表孔径大于1.5nm的微孔和中孔发达程度;而丹宁酸值代表直径大于2.8nm左右的中孔数量;苯酚值体现活性炭表面化学信息,可表征活性炭对于小分子芳环类和极性有机物的吸附能力.硝基苯、甲基叔丁基醚(MTBE)、双酚A(BPA)、腐殖酸以及焦化厂二级生化出水的吸附实验结果均验证了该技术作为水处理活性炭实用选型方法的有效性.  相似文献   
70.
研究了在硫酸介质中、溴化钾催化下 ,碘酸根氧化酸性铬蓝K褪色的最佳条件。其最大吸收波长λmax为 5 2 0nm ,表观摩尔吸光系数为 1 .1× 1 0 4 L·mol- 1·cm- 1,碘浓度在 0~ 3 .6mg/L内呈线性关系。方法用于测定加碘食盐中的碘 ,结果令人满意  相似文献   
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