改进的高锰酸钾法滴定微量甲酸根的可行性研究

对常用高锰酸钾氧化还原法进行了改进,并与微量滴定法相结合,测定微量甲酸根含量.从精密度、准确度、线性范围及灵敏度4个方面分析了该方法的可行性,并将该方法分析结果与气相色谱法分析结果进行了比对.结果表明,该法对3种浓度的甲酸溶液测定结果的相对标准偏差为0.84%～1.8%(n=6).线性范围为100～1 100 mg/L,平均回收率为95.8%.     

药用丁基胶塞灰分的热重分析条件优化

针对药用丁基胶塞的灰分指标,考察了热重分析法的反应温度和恒温时间对测试结果的影响,优化了热重分析法测定胶塞灰分的检测方法. 方法测得的胶塞灰分值相对标准偏差为0.01%,且测试耗时少于1 h. 在缩短检测时间的同时,检测结果的准确性和重现性均优于用方法YBB00262005和方法ASTM D6370-99检测所获得的结果.     

王水水浴消解泡塑吸附电感耦合等离子体质谱测定化探样品中金的条件优化

为了简单、快速地测定化探样品中的金(Au),主要研究了王水水浴消解泡塑吸附,电感耦合等离子体质谱(ICP-MS)测定化探样品中金的方法.经过对前处理过程以及仪器测定过程中影响参数的优化,方法的各项指标均满足分析要求.试验结果:方法的检出限为0.014 ng/g,回收率为91%~102%,通过国家一级标准样品的验证,结果与推荐值吻合,方法的相对标准偏差RSD为3.3%~9.4%.方法适用于化探样品中金的检测.     

电感耦合等离子体发射光谱法测定仿真首饰中镍释放量

建立了电感耦合等离子体发射光谱测定仿真饰品中镍释放量的方法.等离子体流量为15.0 L/min,观察高度为10mm,镍的分析线为231.604 nm.镍含量在0～5 mg/L范围内与仪器响应值呈良好的线性关系,线性相关系数r=0.9999.2.0 mg/L镍标准溶液测定结果的相对标准偏差为1.9％(n=6),方法的检出限为8μg/L.用该方法对参考样品进行测定,测定结果在参考值范围内.     

对食品中铝含量国标测定方法的改进

对国标GB/T 5009.182-2003中样品处理方法做了改进,用干法灰化代替湿法消解,解决了国标方法中由于pH值和高氯酸对显色反应的影响造成检测结果不准确的问题.采用干法灰化-分光光度法测定了食品中的铝含量,测定结果的相对标准偏差为1.6%(n=6),回收率为94.3%～100.7%.该方法适用于大批量食品中铝的快速检测.     

影响离子色谱测量准确性的因素

介绍了离子色谱测量过程中色谱条件的变化、样品前处理方法和操作过程等因素对测量结果准确性的影响,提出了相应的解决措施和校准方法.以实际样品测定为例介绍了样品前处理过程中待测组分浓度和形态的变化,对定量分析结果造成的误差及修正方法.     

超声波提取-火焰原子吸收光谱法连续测定土壤中有效铜铁锌锰

为提高测土配方施肥的测土效率,建立了超声波提取-火焰原子吸收光谱法连续测定土壤提取液中有效态铜、铁、锌、锰的快速检测方法.实验结果表明,该方法加标回收率为77.6%～95.5%,相对标准偏差(RSD)为2.2%～6.5%,测定结果与农业行业标准方法的测定结果无显著性差异.方法具有快速,准确,操作简单等特点,有较好的实用...     

核磁共振波谱法测定片剂中盐酸巴马汀含量

以氘代甲醇为溶剂,马来酸为内标,通过比较马来酸内标峰与盐酸巴马汀定量峰的峰面积,采用核磁共振法测定了黄藤素片中盐酸巴马汀的含量。结果显示,该方法的线性范围为1. 00～10. 00 g/L,相关系数(r)为0. 999 3,定量下限为25. 0 mg/L,检出限为8. 5 mg/L,回收率为98. 5%～104%。测定结果与高效液相色谱法基本一致。该方法操作简便、测定结果准确,且与结构鉴定同步完成,适用于黄藤素片的质量控制。     

微波消解ICP-AES测定废弃线路板中的Cu、Cr、Pb等8种元素

采用微波消解技术对废弃线路板进行消解,应用全谱直谱ICP-AES同时测定Cu、Cr、Pb、Mn、Cd、Ni、Sn和Zn的含量.研究了消解体系和谱线选择对测定结果的影响,测定了分析结果的精密度和方法的检出限和回收率.结果表明:样品分析结果的相对标准偏差小于0.5%,方法检测限范围为0.5885～5.641 μg/L,方法的加标回收率和精密度分别为95.0%～103.3%和0.1%～0.5%.该方法能够同时测定多种元素.     

利用化学指示剂在多相催化反应中进行高通量筛选

 介绍了一种简单的组合化学技术,该技术利用催化反应中产物或反应物导致的化学指示剂的颜色变化快速地指示反应进程. 选用甲基橙为指示剂,分子筛为催化剂,考察了不同反应条件下羧酸的酯化反应,并用气相色谱和高效液相色谱分析方法对实验结果进行验证. 结果表明,利用化学指示剂进行的高通量颜色筛选结果与色谱检测结果很好地吻合,该方法具有简单和高效的特点,可应用于对化学指示剂敏感的反应.     

光电直读光谱法测定高锰不锈钢中硫量的改进

使用Spectro Lab M8光电直读光谱仪所提供的Fe-30不锈钢分析程序测定高锰不锈钢中硫量时,所得测定值均偏低。为此,改用高锰不锈钢国家光谱标准样品和内控样品,重新确定了干扰元素(特别是锰)的基体校正模式及测定硫元素的回归分析曲线。通过7个不同含锰量的不锈钢标准样品的分析验证,证明采用经过改进的方法所得测定值均与认定值一致,其绝对误差值均小于JIS标准的允许差。     

The Application of Atomic Absorption Method as a Flow Detector to Gel Chromatography

Abstract

The applicability of atomic absorption method as a flow detector to gel chromatography was discussed. The effluent from the outlet of a Sephadex G-15 column was directly introduced into a nebulizer of atomic absorption spectrometer. It was found that the atomic absorption flow detector was sensitive and highly selective so as to permit the quantitative determination of metal ions. Some advantageous aspects of this detector were also discussed.     

Optimization of a simultaneous multi-element atomic absorption spectrometer

A variable-size simplex procedure was used to optimize the overall response of a simultaneous multi-element flame atomic absorption spectrometer. Seven factors (air to fuel ratio, slit width, height above the burner head, and four hollow cathode lamp currents) were optimized for copper, iron, manganese, and zinc atomic absorption. A univariate search procedure was used to determine the effect of individual factors on response. The results of the optimization showed that a comprise set of operating conditions must be used when performing multi-element determinations. The atomic absorption sensitivity of the multi-element determination as compared to single-element determination was reduced by a factor of no more than two.     

An improved impaction-graphite furnace system for the direct and near real-time determination of cadmium,chromium, lead and manganese in aerosols and cigarette smoke by simultaneous multielement atomic absorption spectrometry

The design, operating characteristics, and preliminary evaluation of an improved impaction-graphite furnace system, based on a theoretical study of particle size collected, are presented. After direct collection, the graphite furnace from the system is inserted in an atomic absorption spectrometer for analysis by simultaneous multielement atomic absorption spectrometry. This system has the potential for the direct and near real-time (few minutes) determination of metals in aerosols. The system has been preliminarily evaluated using aqueous solutions of chromium, and has then been applied to the determination of cadmium, chromium, lead, and manganese in cigarette smoke. Results show an increase ranging from almost five (lead) to sixteen (cadmium) over background levels.     

Determination of Manganese in Sludge,Alloy, and Soil by Tungsten Coil Atomic Emission Spectrometry

A tungsten coil atomic emission spectrometer (WCAES) was developed and evaluated for the determination of manganese in industrial sludge, alloy, and soil. The system employed a coil extracted from a 150 watts/15 volts commercial slide projector light bulb and a simple power supply that provided a constant current to the coil. The analytical signals were resolved and detected using a Czerny-Turner spectrometer and a charge coupled device. Three manganese emission lines were detected simultaneously. Using different emission lines, limits of detection for manganese varied from 0.54 to 0.65 milligram per liter, and relative standard deviations for manganese at 5 milligrams per liter varied from 5.9 to 8.5 percent (n = 10). Summation of the Mn signals improved the detection limit to 0.17 milligram per liter and decreased the relative standard deviation to 1.7 percent. Spectral interferences were observed in the presence of Al, Ca, K, and Na. The accuracy was determined using two certified reference materials, and the results obtained by WCAES were in agreement with those obtained by inductively coupled plasma-optical emission spectrometry at the 95 percent confidence level.     

直读光谱法测定合金工具钢中铬、锰和钼

建立了ARL-4460直读光谱仪对Cr12、Cr12MoV中铬、锰、钼元素的快速检测方法。使用基体铁作为内标元素,测定标准样品中铬、锰、钼元素的相对强度,减少了外界电压不稳对绝对强度稳定性的影响;由于标准样品中基体铁含量不同,为减少内标元素含量的变化对工作曲线相关系数和估计标准差的影响,使用相对含量校正工作曲线。在优化的实验条件下,试样中三种元素的相对标准偏差分别为0.68%、0.79%和1.7%(n=11)。测定结果与化学分析方法测定结果一致,可实现合金工具钢中铬、锰和钼的快速检测。     

茶叶中微量营养元素的原子吸收光谱分析

茶叶中的微量元素与茶叶的营养和药理作用有密切关系^[1],与茶树生长的生化活动也有密切关系^[2,3]。对茶叶中的微量营养元素的分析有助于了解茶叶的品质,研究茶叶的营养药理作用,促进茶叶生产的发展。为此,我们研究提出了用火焰原子吸收光谱法测定茶叶中铜、锰、铁、锌,方法简便、准确。     

多金属结核/结壳中稀土元素的富集特征及其资源效应

多金属结核/结壳是海洋中最重要的固体沉积矿产之一,蕴藏丰富的铁、锰、铜、钴、镍等金属元素,也是稀土元素的富集体.利用等离子质谱仪/光谱仪对太平洋、大西洋、印度洋及南海北部海多金属结核/结壳11个样品25份试样的稀土含量进行了分析,多金属结核/结壳中稀土平均含量为1265 57×10-6,其中结核平均含量为1096.96×10-6,结壳平均含量1623.88×10-6,人人超过地壳和玑积岩的平均含量.稀土元素的富集主要受控于结核/结壳中铁、锰氧化物及粘土矿物对海水和沉积物中稀土元素的吸附作用,Ce元素高度富集,使其成为多金属结核/结壳矿产开发中可能最先利用的稀土元素之一.     

Multielement Analysis of Whole Blood Using a Capacitively Coupled Microwave Plasma Atomic Emission Spectrometer

A capacitively coupled microwave plasma atomic emission spectrometer (CMP-AES) has been evaluated as a means for the direct analysis of several of the primary and trace elements in whole blood. A tungsten filament spiral electrode was used with the CMP, and whole blood samples were deposited on the electrode and subsequently dried, ashed, and atomized. The emission was measured with a spectrometer and a charge-coupled-device detector. A sample size of only 2 μl was required and the time for each sample run was under 4 min. This method has a wide dynamic range, allowing the determination of both the primary elements in blood and elements present in trace quantities. Potassium, sodium, lithium, magnesium, manganese, and zinc were studied. Good linearity was observed and the concentration levels obtained for these elements were consistent with literature values. The primary advantages of this method are that no sample pretreatment or dilution is required, the instrument cost is low, and the method is capable of simultaneous multielement analysis on small, discrete samples.     

金属镁中杂质元素的快速测定

以盐酸溶液(1 1)溶解金属铗样品,用电感耦合等离子体原子发射光谱(ICP—AES)法同时测定金属镁样品中的杂质元素铁、硅、锰、铝、铜和镍。采用标准溶液与样品溶液基体相一致的方法消除基体干扰。对标准样品进行测定,测定结果与标准值基本一致,相对标准偏差小于7％。t检验结果证明,该方法不存在系统误差。