资料摘要
资料下载土壤全钾含量一般在1~2%左右,其中结构钾(土壤矿物晶格或深受结构束缚的钾)约占90一98%,纷效钾占2—8%,速效钾占0.1—2%。 根据钾的存在状态和植物吸收性能,可将土壤钾素分为四部分:土壤古钾矿物(难溶性钾),非交换性钾(缓效性钾),交换性钾;水溶性钾。后两种钾为速效钾,可直接被作物吸收利用。用1N中性醋酸铵提取的速效钾与钾肥肥效相关性良好,特别是旱地土壤。待液中钾的测定,有重量法、容量法,比色法、比浊法,火焰光度法和原子吸收分光光度法。 现在多采用火焰光度法,因为它们既快速、简便,又灵敏、准确。 (一)1N中性醋酸铵提取—火焰光度法或原于吸收分光光度法的测定原理 以lN中性醋酸铵溶液为浸提剂时,NH4+与土壤胶体表面的K+进行交换,连同水溶液K+(二者合称速效钾)一起进入溶液。浸出液中的钾直接用火焰光度计或原子吸收分光光度计(简称AAS)测定。
GB/T 火焰光度计测定食物中的钾钠含量
简介:4.1 实验室常用设备。 4.2 火焰光度计。 5 操作步骤 5.1 样品处理 精确称取均匀样品干样0.5~1g,湿样1~2g,饮料等液体样品3~5g于250mL高型烧杯中,加20~30mL混合酸消化液,上盖表皿。置于电热板或电沙浴上加热消化。如消化不完全,再补加几毫升混合酸消化液,继续加热消化,直至无色透明为止。加几毫升去离子水,加热以除去多余的硝酸。待烧杯中的液体接近2~3mL时,取下冷却。用去离子水洗并转移到10mL刻度试管中,定容至刻度(也可用测钙、铁、镁、锰的消化好的液样进行钾和钠的测定)。
FP640火焰光度计(英文出口)
简介:1.1 Introduction The flame photometer is an analytical instrument based on the principle that the emission spectrum decides the element. When NaCl, for example, is burned, the flame shows the color of yellow. The reason is that the outer electrons, of the Na atom is generated to a higher level by the flame energy, and when it returns to the normal level, it emits the light spectrum with the specific wavelength---yellow light spectrum with a main wave of 5893A°. The flame photometer is an instrument to measure the intensity of this light spectrum to determine the concentration of the measured element. The flame photometer has the advantage of fast analysis and high sensitivity with little sample consumption. For these reasons, it has been extensively employed in such fields as clinical examination, fertilizer and soil analysis, as well as chemical industry. Theoretically, the intensity of the emitted light spectrum is directly reportional to the concentration of the element. The generated energy, however, will affect the result, so this principle is applicable only when the intensity is low. FP-640’s range: when used in clinical examination is: K 0.02mmol/L-0.08mmol/L, Na 1.20mmol/L-1.80mmol/L; when used in other circumstances, the range can be expanded to meet the need reasonability.
FP6400A火焰光度计
简介:1、 原理简述: 从分子结构理论了解到:原子的外层电子总沿着固定的轨道运行,当受到火焰提供的热能后,其电子就要脱离原先轨道跃迁到受激能级轨道,由于同时又受到原子核的吸引,电子又从受激能级回复到正常状态时,电子就要释放能量.这种能量是以发射出其元素特定波长的光谱来表示.利用测量元素特定光谱的波长的发光强弱来进行元素定性定量的方法就称之为火焰发射光谱分析法,利用火焰光谱分析法制造的分析仪器就叫火焰光度计. 对火焰光度计来讲,虽然理论上被测元素含量与其发射光谱强度成正比,但由于受到激发能量限制,一般只适用于一定浓度范围的碱金属,碱土金属的定量分析.
FP640火焰光度计
简介:1、 原理简述: 从分子结构理论了解到:原子的外层电子总沿着固定的轨道运行,当受到火焰提供的热能后,其电子就要脱离原先轨道跃迁到受激能级轨道,由于同时又受到原子核的吸引,电子又从受激能级回复到正常状态时,电子就要释放能量.这种能量是以发射出其元素特定波长的光谱来表示.利用测量元素特定光谱的波长的发光强弱来进行元素定性定量的方法就称之为火焰发射光谱分析法,利用火焰光谱分析法制造的分析仪器就叫火焰光度计. 对火焰光度计来讲,虽然理论上被测元素含量与其发射光谱强度成正比,但由于受到激发能量限制,一般只适用于一定浓度范围的碱金属,碱土金属的定量分析.
AP1500火焰光度计(英文出口)
简介:I. Working Principles According to the molecular structure theory, outer electrons of atoms always move via a trapped orbit, which they usually move out of and transit to the orbit of the excited level, if they receive the heat energy provided by a flame. At the same time, attracted by the nucleus and recovering from the excited level to the normal level, the electrons release energy which can be illustrated by the spectra that release specific wavelengths. This method, which measures the luminescence levels of the elements to be determined at specific wavelengths through qualitative and quantitative analyses, is called analysis of spectra based on flame emission, and the instrument which applies to this method is called a flame photometer. Theoretically, the contents of the elements to be determined are proportional to the intensity of the spectra released; however, the flame photometer normally applies only to the quantitative analysis of some alkali metals and alkaline earth metals at a certain concentration range, as limited by the excitement energy.
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