电感耦合等离子体质谱法测定垃圾焚烧飞灰中重金属的研究

基于全自动消解仪优化程序,以HNO3-HF-HClO4消解体系消解飞灰样品,通过选择合适的待测同位素以及干扰元素校正方程校正质谱干扰,建立了全自动消解-电感耦合等离子质谱法（ICP-MS）测定飞灰样品中铍、钒、铬、锰、镍、铜、锌、镉、铅等9种元素的新方法。该方法采用嵌片技术和碰撞模式消除基体干扰,采用单一内标103Rh进行信号漂移校正,9种元素校准曲线的线性相关系数均大于0.999,方法检出限在0.01~0.3 μg/g之间。该方法用飞灰标准物质SRM1633C进行验证,平均RSD在0.54%~2.38%之间,加标回收率为85%~120%,各元素的测定值与标准值吻合。该分析方法具有较好的准确度和精密度,适合垃圾焚烧产生飞灰样品中全量金属的测定。     

全自动消解电感耦合等离子体质谱仪测定环境土壤中铍钡铊银

采用HNO3-HF-HCl O_4消解体系,利用全自动消解仪优化的程序消解土样,电感耦合等离子体质谱仪(ICP-MS)碰撞气流速3.0~4.0 mL/min,以7Li,~(103)Rh,~(209)Bi作为内标,通过编辑干扰元素校正方程校正质谱干扰,建立全自动消解电感耦合等离子体质谱仪测定土壤中铍、钡、铊、银4种元素的新方法。结果表明:铍、钡、铊、银校准曲线r0.999,方法检出限在0.005~0.1μg/g之间,RSD为0.19%~2.0%,加标回收率在100.0%~109.2%,该方法用GSS-13和GSS-10标准样品验证,相对误差-3.8%~1.7%,与标准值吻合。采用实验方法对松花江河岸土壤中4种元素进行测定,并用电感耦合等离子体发射光谱法(ICP-AES)进行仪器比对,结果基本一致。     

微波消解-电感耦合等离体子质谱法(ICP-MS)同时测定畜禽粪便中7种重金属元素

粪便样品干燥、研磨后,称取0.25 g样品,加入8 mL硝酸,采用微波消解方法进行前处理。采用KED模式消除质谱干扰,采用内标校正消除非质谱干扰(Ge作为Cu、Zn、Cr的内标,Bi作为Hg和Pb的内标,Rh作为As和Cd的内标),建立了可同时测定畜禽粪便中Cu、Zn、Cr、As、Cd、Pb、Hg 7种重金属元素的微波消解-电感耦合等离子体质谱法。方法线性相关系数均在0.9995以上,检出限为0.005~0.305μg/L,加标回收率为83.6%~112%,相对标准偏差为0.70%~5.6%。方法灵敏度、准确度和精密度高,实用性强,适用于同时检测畜禽粪便中多种重金属元素,对畜禽粪便的科学还田具有指导意义。     

电感耦合等离子体质谱法测定铜冶炼渣尾矿中银及铂族元素的含量北大核心CSCD

样品(0.400 0 g)置于50 mL样品管中,加入盐酸-硝酸-水(3+1+4)混合液10 mL,饱和氟化氢铵溶液1.0 mL,经石墨消解仪斜坡升温进行消解。消解液冷却10 min,用水定容至50 mL。分取10.0 mL,用水稀释至20 mL,所得溶液采用电感耦合等离子体质谱法测定其中银及铂族元素(钌、铑、钯、铱、铂、金)的含量。以标准加入法补偿基体效应制作标准曲线。在质谱分析中采用标准模式。7种元素的检出限(3s)在0.01~0.80μg·L^(-1)之间。按标准加入法进行回收试验,回收率在94.0%~105%之间,相对标准偏差(n=11)在0.70%~2.1%之间。按上述方法分析铜冶炼渣尾矿样品,结果与石墨炉原子吸收光谱法测定结果基本一致。     

电感耦合等离子体质谱法测定铜冶炼渣尾矿中银及铂族元素的含量

样品(0.400 0 g)置于50 mL样品管中,加入盐酸-硝酸-水(3+1+4)混合液10 mL,饱和氟化氢铵溶液1.0 mL,经石墨消解仪斜坡升温进行消解。消解液冷却10 min,用水定容至50 mL。分取10.0 mL,用水稀释至20 mL,所得溶液采用电感耦合等离子体质谱法测定其中银及铂族元素(钌、铑、钯、铱、铂、金)的含量。以标准加入法补偿基体效应制作标准曲线。在质谱分析中采用标准模式。7种元素的检出限(3s)在0.01~0.80μg·L~(-1)之间。按标准加入法进行回收试验,回收率在94.0%~105%之间,相对标准偏差(n=11)在0.70%~2.1%之间。按上述方法分析铜冶炼渣尾矿样品,结果与石墨炉原子吸收光谱法测定结果基本一致。     

石墨消解-电感耦合等离子体质谱(ICP-MS)法测定铜精矿中汞的含量

称取0.2g样品于50mL样品管中,以5mL硝酸-盐酸(1∶1)混合溶液为溶剂,采用石墨消解仪对样品进行前处理。以159 Tb作内标元素补偿基体效应,用电感耦合等离子体质谱(ICP-MS)法对铜精矿中的202 Hg进行测定。结果显示,在0～50μg/L的浓度范围内,校准曲线线性相关系数在0.999 9以上,方法检出限0.019μg/L。对铜精矿标准样品的检测结果与标准值相符。铜精矿中汞的浓度在0.94～15.06μg/g时,与直接测汞仪检测结果对比基本一致。     

电感耦合等离子体质谱（ICP-MS）法测定垃圾焚烧飞灰中的重金属

基于全自动消解仪优化程序,以HNO3-HF-HClO4消解体系消解飞灰样品,通过选择合适的待测同位素以及干扰元素校正方程校正质谱干扰,建立了全自动消解-电感耦合等离子质谱(ICP-MS)法测定飞灰样品中铍、钒、铬、锰、镍、铜、锌、镉、铅等9种元素的新方法。采用嵌片技术和碰撞模式消除基体干扰,采用单一内标~(103) Rh进行信号漂移校正,9种元素校准曲线的线性相关系数均大于0.999,方法检出限在0.01～0.3μg/g。用飞灰标准物质SRM1633C进行验证,平均相对标准偏差RSD在0.54%～2.4%,加标回收率为85%～120%,各元素的测定值与标准值吻合。方法具有较好的准确度和精密度,适合垃圾焚烧产生飞灰样品中全量金属的测定。     

电感耦合等离子体质谱(ICP-MS)法测定锰矿冶炼烟尘中多种重金属元素

为了准确测定锰矿冶炼烟尘中重金属元素的含量,为锰矿冶炼过程中监测和评价环境影响提供有力的数据支撑,本文建立了电感耦合等离子体质谱法测定锰矿冶炼烟尘中的Cr、Ni、Cd、Tl、Pb等多种重金属元素的方法。采用HCl+HNO3+HClO4+HF消解体系对试样进行前处理,通过选用合适的内标溶液消除测定中的非质谱干扰,采用碰撞池模式和编辑校正方程消除质谱干扰,从而确定了最佳实验条件。实验结果表明,各元素标准曲线的线性相关系数均大于0.9999,方法检出限在0.007～0.094 mg/kg之间,样品测定的相对标准偏差(RSD,n=11)在0.43 %～4.93 %之间,样品加标回收率为93.8 % ～107.2%。方法具有操作简便、线性范围宽、检出限低、精密度高等优点,满足锰矿冶炼烟尘中Cr、Ni、Cd、Tl、Pb等多种重金属元素的同时测定要求。     

电感耦合等离子体质谱法测定盐酸头孢卡品酯颗粒中9种元素杂质的含量北大核心CSCD

由于头孢卡品酯的理化性质及其颗粒制剂包含很多难溶的辅料,为准确测定盐酸头孢卡品酯颗粒中镉、铅、砷、汞、钴、钒、镍、钼、铬等9种元素杂质的含量,尤其是挥发性元素汞,需要对样品进行络合和稳定性处理。以6 mL硝酸、1.5 mL盐酸、0.1 mL氢氟酸为消解酸,于180℃微波消解50 mg盐酸头孢卡品酯颗粒样品30 min;消解结束后,反复赶酸,再用体积比为0.1∶100的氢氟酸和盐酸-硝酸-水(体积比为1∶4∶95)的混合液定容至50 mL,采用电感耦合等离子体质谱法测定样品中9种元素杂质的含量,内标法定量。结果显示:9种元素杂质的质量浓度在一定范围内与其对应的响应值与内标响应值的比值呈线性关系,检出限(3s/k)为0.001~0.070μg·L^(-1);对6份同一加标样品溶液进行测定,9种元素杂质测定值的相对标准偏差为2.9%~5.1%;对实际样品进行加标回收试验,回收率为82.0%~104%。方法用于实际样品分析,9种元素杂质的含量均低于元素杂质指导原则规定的允许浓度限值。     

火焰原子吸收光谱法测定铜冶炼渣中镍

通过对铜冶炼渣化学组成和性质的研究,确定了测定镍的实验方法。铜冶炼渣中二氧化硅含量在20%~40%,硫含量10%~20%,样品的分解具有一定的难度,必然影响镍的测定结果,因此需在样品分解过程中加入一定量的氟化氢铵、溴使二氧化硅生成四氟化硅、硫生成硫化氢挥发除去,溶液中其余共存元素主要有铜、银、铁、锌等元素不干扰测定结果,在硝酸(5%)介质中,用火焰原子吸收光谱法测定镍的含量,测定范围为0.01%~1%,加标回收率在99.5%~100.4%,测定结果的相对标准偏差(n=7)在0.61%~1.18%,检出限为0.004μg/mL,方法快速,简捷,能够满足日常生产检测需要。     

微波消解-电感耦合等离子体质谱(ICP-MS)法测定硅石中五种杂质元素

采用微波消解溶解样品,建立ICP-MS法测定硅石中锰、铜、钒、钛、铬5种杂质元素的方法。探讨了溶解样品及消除干扰的最佳方式,选用Sc(10μg/L)为内标,动态反应池(DRC)模式进行测定。方法检出限为0.1mg/kg(51V)~1.66 mg/kg(47Ti),加标回收率在88.6%~109%,相对标准偏差均小于3%。方法快速准确,精密度好,检出限低,适合硅石中5种杂质元素的测定。     

Use of hydroxylamine hydrochloride in the titrimetric determination of manganese in pyrolusite

A procedure is described for the determination of total manganese in pyrolusite. The sample is decomposed with hydroxylamine hydrochloride solution. The residue left after filtration is fused with sodium carbonate and extracted again with hydroxylamine hydrochloride solution. A suitable aliquot is titrated with EDTA at pH 10, with Eriochrome Black T as indicator, after masking of interfering elements.     

"一锅法"N-(2-苯甲酰胺苯基)-水杨醛亚胺/TiCl4·2THF催化乙烯聚合

报道了4个含苯甲酰胺取代的水杨醛亚胺配体: N-(2-苯甲酰胺苯基)-水杨醛亚胺(L1)、 N-(2-苯甲酰胺苯基)-3-甲基水杨醛亚胺(L2)、 N-(2-苯甲酰胺苯基)-3-叔丁基水杨醛亚胺(L3)和N-(2-苯甲酰胺苯基)-3,5-二溴水杨醛亚胺(L4)的合成, 采用 ¹H NMR和HRMS对其结构进行了表征. 在助催化剂甲基铝氧烷(MAO)作用下, 以L3与TiCl₄·2THF为模型催化体系, 在最佳陈化条件(陈化温度为25 ℃, 陈化时间为30 min, 配体与TiCl₄·2THF的摩尔比3∶1)下, 考察了L1~L4/TiCl₄·2THF催化体系Al/Ti摩尔比、 反应时间、 反应温度和聚合压力, 以及配体结构等对乙烯聚合的影响. 结果表明, 随着在水杨醛骨架上氧原子邻位取代基位阻的增大, 催化体系的活性及所得聚乙烯的分子量均有增加, 其中以L3的催化活性最高, 达到224 kg PE/(mol Ti?h). 采用高温 ¹H NMR, ¹³C NMR, GPC-IR和DSC等对由不同配体L1~L4/TiCl₄·2THF得到的聚乙烯样品的微观结构与热性能进行了分析与表征, 结果显示样品为线性高密度聚乙烯, M_n=5.9×10 ⁴~11.9×10 ⁴, 分子量分布(PDI)为21.9~72.1.     

Indirect ultraviolet determination of silver with nickelocyanide ion by flow injection analysis

A flow-injection method for the ultraviolet spectrophotometric determination of silver, based on its reaction with nickelocyanide ion, Ni(CN)²⁻₄, in ammoniacal buffer medium (pH 10) and subsequent measurement of the decrease in the absorption of the Ni(CN)²⁻₄ complex at 275 nm is described. The calibration graph is linear in the range 10–400 μm silver. At a sampling rate of about 60 samples h⁻¹ with 35 μl sample injections, precision was about 1% relative standard deviation. The proposed method was successfully applied to the determination of silver in some common silver minerals.     

Removal of interferences in the speciation of chromium using an octopole reaction system in ion chromatography with inductively coupled plasma mass spectrometry

When inductively coupled plasma mass spectrometry (ICP-MS) is used for the detection of ⁵²Cr (83.8%) species in ion chromatography (IC), interference from polyatomic ions such as ⁴⁰Ar¹²C⁺ and ³⁵Cl¹⁶O¹H⁺, often occurs due to their mass at m/z 52. To address the issue, an octopole reaction system (ORS) in ICP-MS, including He and H₂ modes, was used to determine whether the background and interference from polyatomic ions could be reduced in the detection of ⁵²Cr. Compared to standard mode, the polyatomic ions were reduced by either He or H₂; for example, more than 97 and 98% of ³⁵Cl was removed using a He and H₂ tune, respectively. However, the detection sensitivity for ⁵²Cr was decreased, for example, the sensitivity was 27.95 and 67.02% of the standard mode for Cr(EDTA)₂⁻using a He and H₂ tune, respectively. The H₂ tune is recommended for the detection of ⁵²Cr at a flow rate of 2.0 mL/min with detection limits in the range of 0.2–0.4 μg/L. The developed method was used to measure chromium speciation in waters containing high concentration of chloride.     

Use of p-dimethylaminobenzalhyde as a colored reagent for determination of procaine hydrochloride by spectrophotometry

Spectrophotometric determination of procaine hydrochloride is described. The procaine hydrochloride reacts with p-dimethylaminobenzalhyde in glacial acetic acid to form an Schiff base which is a yellow compound, and its maximum absorption wavelength is at 455nm, ₄₅₅=3.46×10⁴. The absorbance for procaine hydrochloride from 0.2 to 15 μg ml⁻¹ obeys Beer's law. The linear regression equation of the calibration graph is C=5.866A−0.02, with a linear regression correlative coefficient is 0.9994 and relative standard deviation (RSD) of 1.7%; the detection limit is 0.1 μg ml⁻¹; recovery is from 92.0 to 110.0%. Effects of reaction medium, temperature, gentamycin, beneylpenicillin, kanamycin, streptomycin, foreign ions, and stand for time on the determination of procaine hydrochloride have been examined. The results obtained by this method agreed with those by the official method (dead-stop titration). This method is rapid and simple, and can be used for the determination of procaine hydrochloride in injection solution of procaine hydrochloride.     

水杨酸盐敏化BaF2∶Tb3+纳米粒子中的Tb3+离子发光

采用水热法制备了均匀、单分散的BaF₂∶Tb³⁺纳米粒子,并采用离子交换法制备了水杨酸钠敏化的BaF₂∶Tb³⁺纳米粒子(SS-BaF₂∶Tb³⁺)。 系统地研究了样品的结构、形貌和光致发光性质。 结果表明,监测Tb³⁺离子在547 nm的⁵D₄→⁷F₅跃迁,SS-BaF₂∶Tb³⁺纳米粒子获得了从200 nm到385 nm波长范围宽的激发带;激发SS的π-π^*电子跃迁吸收,由于SS到Tb³⁺的能量传递(“天线效应”),SS-BaF₂∶Tb³⁺纳米粒子产生了增强的Tb³⁺离子绿光发射;敏化纳米粒子中Tb³⁺离子光致发光寿命比未敏化纳米粒子中Tb³⁺离子寿命长。     

Use of factorial experimental design for the rapid evaluation of main and interactive factors affecting linearity in calibration curves for sulfate analysis by ion chromatography

Analytical results of anion determination by suppressed ion chromatography are significantly affected by calibration curve calculation. In this paper, as expected, eluent pK_a is shown to influence calibration linearity in the range 1–20 mg/l sulfate, with A carbonate-hydrogencarbonate mixture producing a larger non-linearity than NaOH. Evidence is given for very large errors (about 30–40%) in estimating sample sulfate concentration when linear regression is used instead of a quadratic calibration curve. This study was performed following a 2⁴ run full factorial experimental design, including eluent pK_a, counterion type, solution composition and current level for background suppression as main variables.     

Direct solid sampling electrothermal vaporization of alumina for analysis by inductively coupled plasma optical emission spectrometry

A procedure based on electrothermal evaporation (ETV) and inductively coupled plasma atomic emission spectrometry (ICP-OES) for the determination of trace impurities in Al₂O₃ powders without any sample pretreatment is presented. With the aid of matrix modifier the transport and the evaporation efficiency for refractory compounds could be increased by forming halides with a lower boiling point. As calibration is still a problem in direct solid sample analysis, different calibration approaches including the use of certified reference materials from NIST and standard addition of aqueous solutions of analytes were discussed. The accuracy obtained with calibration and with the standard addition method was shown up for the elements Ca, Fe, Ga, Mg, Mn, Na, Ni and V for the case of Al₂O₃ NIST standard reference material (SRM 699). The ETV–ICP-OES method was used for the analysis of Al₂O₃ powders with impurities in the low μg/g range and the results for the elements Ca, Fe, Ga, Mg, Mn, Na, Ni and V obtained with evaporation of discrete powder amounts with ETV–ICP-OES and slurry evaporation under the use of ultrasonic homogenization during the sampling and ETV–ICP-MS were shown to be in a good agreement.