共查询到20条相似文献，搜索用时 93 毫秒
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《中国饲料》2020,(5)
为建立全自动烷基汞分析仪测定饲料中甲基汞和乙基汞的方法 ,实验样品经氢氧化钾/甲醇溶液提取后,使用四丙基硼化钠作为衍生试剂进行丙基化反应,然后用全自动烷基汞分析仪进行检测。结果表明:甲基汞和乙基汞在标准曲线范围内线性关系良好,线性相关系数均大于0.9995,甲基汞的方法检出限为3μg/kg,方法定量限为8μg/kg,相对标准偏差(n=7)为4.58%,平均回收率为91.1%～98.2%;乙基汞的方法检出限为4μg/kg,方法定量限为13μg/kg,相对标准偏差(n=7)为5.19%,平均回收率为88.5%～95.7%。此方法简单、快速、准确度好、灵敏度高,适用于饲料中甲基汞和乙基汞的测定。 相似文献
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高效液相色谱法和气相色谱质谱法测定生鲜牛乳中三聚氰胺残留量 总被引：1，自引：0，他引：1
运用高效液相色谱法(HPLC)和气相色谱质谱法(GC/MS)测定生鲜牛乳中三聚氰胺残留量,HPLC法筛选和定量,二极管阵列检测器法和GC/MS法进行确证分析定性。生鲜牛乳中的三聚氰胺经三氯乙酸提取,阳离子交换柱净化,配备二极管阵列检测器的高效液相色谱仪进行定量测定;试样通过衍生化,采用EI电离源方式进行选择离子扫描(SIM),选择离子为99、171、327和342。HPLC法三聚氰胺的检出限为0.1mg/kg(S/N>3),线性范围为0.2～50.0μg/mL,在添加浓度为0.2～1.0mg/kg的水平上回收率为95.2%～98.3%,相对标准偏差(RSD)(n=5)为1.92%～4.59%;GC/MS法三聚氰胺的检出限为0.05mg/kg,线性范围为0.05～2.0μg/mL,在添加浓度为0.1～0.5mg/kg的水平上回收率为89.8%～96.5%,RSD(n=5)为3.46%～8.08%。本方法具有灵敏度高、实用性强、提取简单等优点。 相似文献
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为了建立了高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)法测定生猪粪便中亚砷酸盐As(Ⅲ)、砷酸盐As(Ⅴ)、一甲基砷(MMA)、二甲基砷(DMA)、对氨基苯胂酸(p-ASA)、硝羟苯胂酸(ROX)和卡巴胂(carbarsone)7种砷形态,采用1 mmol/L K_2CO_3溶液:甲醇(90∶10,V/V)作为提取剂超声水浴提取样品,以DionexIonPac AS7作为分析柱,(NH_4)_2CO_3溶液作为流动相梯度洗脱,对生猪粪便中的砷形态化合物进行分析测定。结果显示:7种砷形态化合物在19 min以内达到基线分离,标准曲线线性相关系数(R~2)均大于0.999,方法的检出限为0.004～0.014 mg/kg,RSD均小于5%,平均回收率为81.6%～107.0%。通过对实际样品的分析,生猪粪便中砷主要以As(Ⅲ)、As(Ⅴ)和DMA等形态存在,常用的有机砷制剂检测出了p-ASA。 相似文献
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采用液相色谱-串联质谱法测定鸡蛋中多西环素的残留量.用0.01 mol/L的乙二胺四乙酸二钠溶液和0.3%磷酸溶液为提取液,三氯乙酸溶液为蛋白沉淀剂,离心后上清液经HLB固相萃取柱净化、浓缩.色谱柱为Agilent C18柱(150 mm×2.1 mm i.d,5 μm);以0.1% 甲酸溶液、甲醇为梯度洗脱流动相.标准曲线的线性范围为0.01～0.5 μg/mL.经3种不同浓度回收率的测定,其回收率在79.7%～86.6%之间,RSD小于7.7%(n＝5).检测限为4 μg/kg.测定结果产蛋鸡用0.02%多西环素溶液饮水,连用5 d,投药量为每只鸡45.45 mg/d,在用药第3、4、5天,其鸡蛋中残留量分别为0.94、0.67、0.27 mg/kg,均高于国家规定的MRL 0.20 mg/kg;停药后,多西环素在鸡体内残留消除缓慢. 相似文献
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试验旨在使用无记忆效应氢化物发生原子荧光仪测定饲料中汞的含量。采用联合研发的原子荧光光度计，建立一种以水为载流无记忆效应氢化物发生原子荧光法检测饲料中汞的方法。从4种混合酸中优选出HNO3-H2O2(1∶1)作为消解体系，选用2 mL 220 g/L氨基磺酸溶液消除了氮氧化合物的干扰。建立的方法在0.2～1.0μg/L范围内线性良好，相关系数r=0.999 6，检出限(n=11)为0.003 1μg/L，相对标准偏差(n=7)为2.28%，加标回收率93%～99%。研究表明，试验所用方法具有灵敏度高、准确高效等优点，可实现饲料中汞含量的快速检测。 相似文献
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鱼粉中砷消解方法的优化 总被引：2，自引：0，他引：2
应用原子荧光法测定鱼粉中砷,分别运用干式灰化法、微波消解法和湿法消解3种前处理方法对样品进行消解并测定砷的含量。采用硝酸-高氯酸-硫酸体系进行湿法消解,检测鱼粉样品中的总砷,检测结果与中国合格评定国家认可委员会组织的鱼粉中重金属含量的测定(CNAS T0508)能力验证中位值相近(相对偏差=0.42%);相对标准偏差(n=6)0.39%;加标水平20 mg/kg,平均回收率98.02%～103.05%;检出限3.6μg/kg;线性范围80～450μg/mL,R2=0.998 2。结果表明:对于鱼粉这类难消解样品,采用硝酸-高氯酸-硫酸体系进行湿法消解,消解能力强,处理效果较好,检测灵敏度、准确度和精密度均能满足分析要求。 相似文献
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Beran GW 《Preventive veterinary medicine》2008,86(3-4):198-207
When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures. 相似文献
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Dekker A Dercksen D Snoep J van Wuyjckhuise L 《Tijdschrift voor diergeneeskunde》2007,132(18):695-701
On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures. 相似文献
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在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。 相似文献
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