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油菜能将吸收到的无机硒63.8%转化为有机硒,叶面喷施富硒康(1:500)可使产量提高27.02%,含硒量可达87.8μg/kg,比对照增加4.55倍。针对青菜保鲜问题,运用BA保鲜技术对油菜进行处理,可使保鲜期延长4-5天。 相似文献
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植物中有机硒含量的测定 总被引:4,自引:0,他引:4
秦Fang 《无锡轻工大学学报(食品与生物技术)》1998,17(4):74-77
对有机硒和无机硒的测定进行了探讨,利用压榨提取无机硒用荧光二阶导数法进行硒的定量测定,通过标准添加法对提取率进行了测定,回收率为93.2%~98.4%变异系数为1.86。 相似文献
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Ramazan Gürkan Halil brahim Ulusoy Mehmet Akay Pinar Bulut Ramazan Gurkan Halil ibrahim Ulusoy Mehmet Akcay Pmar Bulut 《稀有金属(英文版)》2011,30(5):477-487
A novel catalytic kinetic method is proposed for the determination of Se(IV), Se(VI), and total inorganic selenium in water
based on the catalytic effect of Se(IV) on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The
fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the
two calibration graphs are linear with a good correlation coefficient in the range 2–20 and 20–200 μg·L−1 of Se(IV) for the fixed-time method at 30°C. The experimental and theoretical detection limits of the developed kinetic method
were found to be 0.21 and 2.50 μg·L−1 for the fixed-time method (3 min). All of the variables that affect the sensitivity at 645 nm were investigated, and the
optimum conditions were established. The interference effect of various cations and anions on the Se(IV) determination was
also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange
resin such as Amberlite IR120 plus as long as chelating agents of thiourea and thiosulphate. The proposed kinetic method was
validated statistically and through recovery studies in natural water samples. The relative standard deviations (RSDs) for
ten replicate measurements of 2, 10, and 20 μg·L−1 of Se(IV) change between 0.35% and 5.58%, while the RSDs for ten replicate measurements of 3, 6, and 12 μg·L−1 of Se(VI) change between 0.49% and 1.61%. Analyses of a certified standard reference material (NIST SRM 1643e) for selenium
using the fixed-time method showed that the proposed kinetic method has good accuracy. The Se(IV), Se(VI), and total inorganic
selenium in lake and river water samples have been successfully determined by this method after selective reduction of Se(VI)
to Se(IV). 相似文献
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通过建立一种基于分散微固相萃取(D-μ-SPE)技术的高灵敏度和高特异性方法,用于测定环境水样中的无机硒。采用非常简单且快速的预富集方法,即利用纯纳米二氧化硅萃取与吡咯烷二硫代氨基甲酸铵(APDC)络合的Se(Ⅳ)。用乙酸乙酯洗脱纳米SiO2中的Se(Ⅳ),然后通过电热原子吸收光谱法(ETAAS)进行测定。在形态分析方面,预还原步骤后基于总无机Se和Se(Ⅳ)之间的浓度差异,选择性地对于Se(Ⅳ)进行定量。并对pH值、离子强度、螯合剂种类等因素进行优化,最终得到92%的保留率,最佳优化条件为pH=2.0、4.8μmol/L的APDC和使用1 mg纳米SiO2为吸附剂。基于10 mL样品的研究结果得出:LOD为1.2 ng/L,LOQ为4.2 ng/L,相对标准偏差为3.6%。本研究方法最终可用于不同来源和成分的环境水样,包括自来水、雨水、地下水和江水。 相似文献
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对活性干酵母的耐Se、富Se性能作了探讨,并初步研究了酵母转化无机Se为有机Se的营养与环境条件.结果表明活性干酵母具有很强的耐Se、富Se能力,是生产富Se酵母的好菌种;无机Se添加量和培养时间等是影响活性干酵母Se转化能力的主要因素,在适宜的摇瓶发酵条件下富Se酵母干重、Se含量和转化率分别可达15.8g/L,790.0μg/g和83.2%. 相似文献
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竹荪多糖产生条件及其对无机硒的转化 总被引:3,自引:0,他引:3
本文筛选了在深层发酵条件下竹荪多糖产量最高的培养基,得到了竹荪多糖产生曲线,并初步测定了竹荪对无机硒的转化率。用正交试验,确定发酵瓶配方为:麦芽糖2%,玉米粉1%,酵母膏0.2%,KH_2PO_40.3%,MgSO_40.15%,以粽子叶煮汁(20%)配制,自然pH。以DNS法测糖,确定多糖产生曲线。以3ppm时竹荪对硒的转化率最高。 相似文献
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在 p H2~ 3、60℃水浴下 ,硒与 3,3’-二氨基联苯胺 ( DAB)反应 ,形成稳定的 Se- DAB络合物 ,显色反应在2 0 min内完成。在 p H7.0~ 7.5时 ,通过甲苯萃取 ,在该体系中络合物最大吸收波长为 42 0 nm。 相似文献