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预混合饲料中铜的测定方法 总被引:1,自引:0,他引:1
在国家饲料检测标准中,测定预混合饲料中铜的含量,使用的仪器为原子吸收光度计.对于大多数饲料生产厂家及养殖场,只拥有分光光度计,一般来说,他们无法检测预混合饲料中铜的含量.笔者根据冶金工业测定铜的方法,经过比较和改进,设计出一套可用分光光度计测定预混合饲料中铜的含量的方法,以供生产厂家及用户参考.1 方法原理将试样灰化,使铜游离出来,在pH9.0—9.5的氨性介质中,用柠檬酸络合铁消除干扰,铜与双环己酮草酰二腙形成蓝色络合物,在波长600nm下进行比色测定. 相似文献
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预混合饲料中铜的测定方法 总被引:1,自引:0,他引:1
预混合饲料中铜的测定方法上海申江饲料添加剂厂刘文彬在国家饲料检测标准中,测定预混合饲料中铜的含量运用的仪器为原子吸收光度计。对于大多数饲料生产厂家及养殖场,只拥有722型或GW-751型或类似的分光光度计,一般来说,他们无法检测预混合饲料中铜的含量。... 相似文献
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<正> 铜、铁的测定方法虽多,但对预混料中铜、铁的测定目前尚未见有报道。为此,本文介绍一种简便、快速的检测预混料中铜、铁含量的方法。 1.原理在碱性氨溶液中,铜能形成Cu(NH_3)_2~(2+)络离子而进入溶液,铁则形成氢氧化铁的沉淀。过滤试液,进入滤液的铜可用碘量法来测定,然后用稀盐酸来溶解沉淀物,使铁进入溶液,用重铬酸钾法来测定铁。 2.测定方法称取1.0000克试样,加水15毫升,浓氨水20毫升,固体氯化铵0.5克,搅匀。放置15分钟后过滤,用1%NH_4Cl—1%NH_3·H_2O混合溶液洗涤烧杯和沉淀物3~4次。滤波用200毫升碘量瓶承接,加浓硫酸5毫升于滤液中,在电炉上蒸至白烟冒尽(以除去有机物)。取下后加入蒸馏水20毫升,加热至微沸,加pH5.5的NaAc—HAC缓冲溶液10毫升,固体碘化钾1~2克,在暗处放置3~5分钟,然后用硫代硫 相似文献
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《畜牧兽医杂志》2021,(2)
试验用火焰原子吸收光谱仪测定了铁含量较高的蛋鸡浓缩饲料和蛋鸡微量元素预混合饲料试样中的铬含量,然后持续增加试样中铁离子的浓度测定铬含量以考察铁离子对铬的干扰,最后在溶液中加入10 mL10%的氯化铵溶液作为铁离子的隐蔽剂以考察氯化铵溶液对铁离子的抗干扰作用,研究分析了三种试验条件下铁离子对铬的干扰以及氯化铵对铬测定的抗干扰情况。试验结果表明:与对照组相比较,持续提高试样溶液中铁离子浓度对铬测定的结果影响不显著;在铁离子浓度较高的试样溶液中加入氯化铵消除铁对铬的干扰效果也不显著。这一试验结果揭示了铁离子对铬测定的干扰以及氯化铵降低铁离子对铬测定的抗干扰情况,为广大饲料检测人员在日常检测中提供借鉴和参考。 相似文献
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铜是饲料工业分析中的一个重要项目 ,定量分析采用原子吸收、等离子体发射光谱和X—射线荧光光谱法等 ,仪器设备昂贵 ,难以普及。笔者在常规铜的DDTC萃取光度法的基础上 ,研究提出铜的巯基棉富集—Cu(DDTC) 2 —萃取光度测定法 ,应用于饲料中铜的测定 ,具有简化操作 ,实现一次萃取 ,节约氯仿 ,环境污染轻 ,灵敏度、精密度高等优点 ,可很好地快速测定饲料中的铜 ,可供饲料厂及养殖厂推广应用。1 检测方法1 1 主要试剂和仪器 2 0 μg/mL铜标准溶液 ,pH 8 5的 5 %EDTA二钠— 2 0 %柠檬酸铵混合溶液 ,1 %DDTC的 0 … 相似文献
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在国家饲料检测标准中,测定预混合饲料中锌含量使用的仪器为原子吸收分光光度计.而大多数饲料生产厂及养殖场,只拥有分光光度计,无法检测市场上预混合饲料中锌含量.笔者根据测定铝合金中锌含量的方法,经过比较和改进,设计出一套可用分光光度计测定预混合饲料中锌含量的方法,供生产厂及用户参考. 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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近几年,世界饲用添加剂市场增长较快,预计今后将进一步增长,据世界粮农组织(FAO)首领会议的倡议,到2015年,将使世界营养不良的人口削减一半,其间,肉制品将会以每年2%的速度增长,特别是加快猪肉和禽肉增长。这将促进世界添加剂,尤其是蛋氨酸和赖氨酸需求量的增加。 相似文献
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