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荧光法测定水样中的硒(Ⅳ)、硒(Ⅵ)和有机硒 总被引:8,自引:0,他引:8
本文提出了水样中硒(Ⅳ)、硒(Ⅵ)和有机硒的荧光测定方法。基于酸性介质中2,3-二氨基萘与硒(Ⅳ)的选择性反应,直接测定硒(Ⅳ);利用盐酸还原硒(Ⅵ)和HNO3-HClO4消化有机硒后,用差减法分别测出硒(Ⅵ)和有机硒。检出限0.07μg/L,线性范围0~10μg/L。硒(Ⅳ)、硒(Ⅵ)和有机硒的相对标准偏差与回收率分别为2.4%和98.5%~101.5%、3.1%和94.8%~103%、4.0%和94.5%~98.8%。 相似文献
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硒酵母中有机硒及硒代氨基酸含量的测定方法 总被引:32,自引:0,他引:32
报道了人工培养硒酵母中有机硒及硒代胱氨酸(SeCys)和硒代蛋氨酸(SeMet)含量的测定方法。采用透析处理法使硒酵母中的无机硒和有机硒得以分离,并采用催化分光光度法测定了硒酵母中有机硒的含量;采用氨基酸自动分析仪测定了硒酵母中SeCys和SeMet的含量。 相似文献
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富硒香菇中微量元素硒的含量测定 总被引:5,自引:0,他引:5
以香菇为载体,通过在培养基中加入一定质量浓度的复合硒溶液进行富硒栽培,获得了富硒香菇,并成功提取出香菇硒多糖,应用2,3-二氨基萘荧光分光光度法测定了富硒香菇中的硒含量,方法简单,结果可靠。 相似文献
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Kenji Soda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):461-472
Abstract We discovered peculiar enzymes participating in selenium amino acid metabolism: selenocysteine β-lyase occurring in mammalian tissues and bacteria, and D-selenocystine α,β-lyase occurring in Clostridium sticklandii. We here describe enzymological properties and reaction mechanisms of these enzymes. We synthesized the selenocysteine analogues of Neurospora crassa copper metallothionein as well as four diastereoisomers of glutathione. Their physicochemical properties and reactivity with peroxides are also described. 相似文献
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Han Hu Dr. Fangchao Liu Zhongli Shen Rui Yan Prof. Dr. Zhengwen Fu 《ChemistryOpen》2022,11(3):e202100296
Selenium (Se) is an element in the same main group as sulfur and is characterized by high electrical conductivity and large capacity (675 mAh g−1). Herein, a novel ultra-high dispersion amorphous selenium graphene composite (a-Se/rGO) was synthesized and a selenium nanorods graphene composite (b-Se/rGO) was prepared by hydrothermal method as the cathode material for all solid-state lithium−selenium (Li−Se) batteries, hoping to improve the efficiency and utilization rate of active substances in all solid-state batteries. The all-solid-state batteries were assembled using a heated thawing electrolyte (2LiIHPN−LiI; HPN=3-hydroxypropionitrile). The utilization rate of a-Se/rGO was 103 % and the capacity was 697 mAh g−1, which remained at 281 mAh g−1 (41.6 % of the 675 mAh g−1) after 30 cycles under 0.5 C. Notably, a-Se/rGO showed excellent performance concerning its utilization rate, with a capacity of up to 610 mAh g−1 at 2 C, due to the high availability of amorphous Se and the special properties of the electrolytes. However, in the charge and discharge cycles, the second discharge capacity of a-Se/rGO was more significantly attenuated than that of the first discharge due to the formation of larger crystals of selenium during the charging process. The battery assembled using b-Se/rGO maintained a capacity of 270.58 mAh g−1 after 30 cycles (the retention rate of discharge capacity was 66.13 % compared with that in the first cycle). Through TEM and other relevant tests, it is speculated that amorphous selenium is conducive to capacity release, which, however, is affected by the formation of crystalline selenium after the first charge process. 相似文献
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硒是人体必需微量元素,它参与抗氧化酶谷胱甘肽过氧化物酶和多种硒蛋白的组成,在体内发挥消除自由基、抗氧化物等作用。硒的抗衰老与抑制肿瘤细胞生长的作用是通过它对端粒酶的作用而实现的。研究端粒酶的调控及其与细胞凋亡的关系已成为人类种瘤研究的新热点。 相似文献
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建立了直接碘量法测定粗硒中硒的分析方法,采用硝酸、硫酸分解试料,在含有酒石酸的6 mo L/L盐酸溶液中,用盐酸羟胺还原析出单体硒,过滤,与其它元素分离,单体硒用酸溶解,在硫酸介质中,用硫代硫酸钠标准溶液进行滴定。临近终点时加入碘化钾,反应析出的碘以淀粉为指示剂,继续用硫代硫酸钠标准滴定溶液进行滴定来测定粗硒中的硒量。方法测定范围70.00%~98.00%,方法相对标准偏差0.084%~0.18%,加标回收率98.8%~100.6%。 相似文献
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微量元素硒的抗癌作用 总被引:1,自引:0,他引:1
对硒在恶性肿瘤的防治及其作用机理进行了总结和讨论,硒通过调节机体免疫功能、介入致癌物的代谢、抑制癌细胞生长及抗过氧化作用等发挥防癌和抗癌功能。另外,硒对白血病的治疗引起了人们的重视。 相似文献
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硒的分析方法研究 总被引:3,自引:1,他引:2
丘基祥 《广东微量元素科学》2002,9(12):43-45
硒是一种分散的稀有元素,它在电子工业,医疗等部门有广泛的用途和诱人的发展前景。本文介绍了一些硒的定性和定量分析方法。 相似文献
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硒与心血管疾病 总被引:5,自引:0,他引:5
曹丹阳 《广东微量元素科学》2005,12(7):1-4
介绍了硒的生物学特征及与心血管疾病的关系,包括:硒的生物学特征及作用,硒与自由基,硒与动脉粥样硬化,硒与冠心病,硒与克山病. 相似文献
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Measured (n = 36, 51 ·g/day) and estimated (n = 274, 44 ·g/day) dietary daily intake of selenium in Turkey is low compared to the RDA value of 55 ·g Se/day. When the existence
of high prevalence of iodine deficiency in most part of the country is considered, adequate level of dietary Se becomes more
important. We have found recently that high iodine-deficient goitrous children had lower Se levels and antioxidant enzyme
(AOE) activities, and higher levels of DNA base lesions than non-goitrous controls.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献