钯作基体改进剂FIA—HG—GFAAS法测定锗及其机理研究

采用钯，钯－镁作基体改进剂，ＦＩＡ－ＨＧ－ＧＦＡＡＳ法成功地测定了锗。灵敏度，精密度和分析速度都得到很大的提高，峰值吸收的特征质量８．０ｐｇ，检出限１０．９ｐｇ，相对标准偏差０．３４％，同时探讨了基体改进剂钯的稳定作用机理及锗在石墨管中的原子化机理。     

钯作基体改进剂FIA－HG－GFAAS法测定锗及其机理研究

采用钯，钯－镁作基体改进剂，ＦＩＡ－ＨＧ－ＧＦＡＡＳ法成功地测定了锗。灵敏度、精密度和分析速度都得到很大的提高。峰值吸收的特征质量８．０ｐｇ，检出限１０．９ｐｇ，相对标准偏差０．３４％，同时探讨了基体改进剂钯的稳定作用机理及锗在石墨管中的原子化机理。     

低温多酸溶样-电感耦合等离子体原子发射光谱法测定核用锆材中锗

采用低温多酸无锗损失的样品预处理后,利用电感耦合等离子体原子发射光谱(ICPAES)测定锆合金中锗。对仪器参数以及被测元素的谱线选择进行了讨论。在选定最佳条件下,铁和铬对锗的测定无影响,基体元素锆和合金元素锡对锗测定的影响可以分别采用基体匹配和与ICP-MS法的测定结果进行对比。在选定的仪器工作条件下,对锆合金试样中锗含量进行多次测定,考察了方法检出限、精密度及加标回收率等,方法相对标准偏差小于2%(n=11),回收率为97%~109%。该方法可成功应用于锆合金中锗以及其他主成分的快速检测。     

石墨炉原子吸收光谱法测定锡和锗时基体改进剂硝酸钙的作用

石墨炉原子吸收光谱法测定低温易挥发元素锡和锗时灵敏度较低。本文以硝酸钙为基体改进剂,使锡和锗的灵敏度分别比不加基体改进剂时提高9倍和50倍,同时也显著提高灰化温度,并降低原子化温度。本文也探讨了基体改进剂硝酸钙对锡和锗的增感机理。锡的增感是由于固相和气相中钙的作用,而锗的增感仅是气相钙的作用。     

石墨炉原子吸收光谱法测定灵芝饲料中痕量锗

研究了用石墨炉原子吸收光谱法测定灵芝饮料中痕量锗，提出了以ＮａＯＨ，Ｈ２Ｏ２为消解液分解样品，采用ＮａＯＨ＋Ｎｉ（ＮＯ３）２混合基体改进剂在热解涂层石墨管中直接测定灵芝饮料中痕量锗的方法，该法简单，快速，灵敏度高，重现性好。     

钴和硝酸镁作为通用基体改进剂的研究

研究钴和硝酸镁作通用基体改进剂的可能性，文中提出了基体改进剂使银，砷，金，镉，镓，锗，铟，铅，锑，硒，锡，铊等元素在石墨炉原子吸收中允灰化温度大的提高，从而消除基体干扰。对钴和硝酸镁作基体改进剂与常用的基体改进剂进行了比较，结果令人满意。     

石墨炉原子吸收光谱法测定有机锗饮品中锗

运用石墨炉原子吸收光谱法测定有机锗饮品中有机锗和无机锗的含量，并对试验条件的优化进行了探索，对总锗的测定只作简单的稀释，应用钯作为基体改进剂，提高了检测灵敏度和回收率，有机锗和无机锗回收率分别在97％－99％和95％－103％之间，RSD均小于5．0％。方法简便、快速、重复性好。     

石墨炉原子吸收法测定人体血尿和尿中锗

研究了口服有机锗后人体血浆及尿中锗的测定方法。以５％三氯乙酸溶液沉淀血蛋白，离心分离后，取上清液测定。以钯和硝酸镍混合溶液做基体改进剂，提高灰化温度至１４００℃，消除了样品中大量基体对测定锗的干扰，方法特征量为３１ｐｇ，检出限为２８ｐｇ（３σ），样品加标准回收率为：血浆９１．４％￣９７．０％，尿９７．２％￣１０５％。     

石墨炉原子吸收法测定有机锗化合物和煤飞灰中痕量锗

本文以硝酸钙为基体改进剂,研究了石墨护原子吸收法测定有机锗化合物和煤飞灰中的痕量锗,同时还研究了各种基体及溶液介质对测定结果的影响。所建立的方法具有简单快速灵敏的特点,适应于测定某些样品中的痕量锗。     

电热原子吸收光谱测定锗时钯的基体改进作用及在食品分析中的应用

本文建立了钯为基体改进剂,电热原子吸收法测定食品中微量锗的方法。该法的检测限为22×10~(-13)g,特征量为8×10~(-13)g。讨论了钯基体改进剂提高锗灵敏度和灰化温度的机理,认为主要是灰化阶段锗与钯在石墨管表面发生固相反应的结果。     

Investigation on the Thermostability of Germanium and Elimination of Chloride and Sulfate.Interference on Germanium in Graphite Furnace Atomic Absorption Spectrometry

TheadvantageofdeterminationoftraceGebyGF.AASisthatonlyafewmicrolitersofsampleisused.Butthematrixinterference,especiallychlorideionandsulfateionisveryseriousl.Sothereisanimportantsubjectforfurtherinvestigatingtoeliminatetheseinterferences.Nitricacidisanoxidant.ThetetravalentGeisstabilizedowingtoitsoxidation.ThemagnitudeoftheGesignalvarieswiththeconcentrationofnitricacidandthemaximumoftheGesignalisobservedwith0.6mol/Lnitricacid.Theactionofsomenitratesissimilarbuttheconcentrationofvariousnit…     

石墨炉原子吸收光谱法测定饮料中的锗及基体干扰的研究

本实验以硝酸镍为基体改进剂，用塞曼石墨炉原子吸收法测定样品中的微量锗，研究了溶液介质与共存元素对测定的影响。方法简便，准确快速，灵敏度高。     

Direct determination of germanium in botanical samples by graphite furnace atomic absorption spectrometry with palladium-zirconium as chemical modifier

A method has been described for the direct determination of trace levels of germanium by graphite furnace atomic absorption spectrometry (GFAAS) using chemical matrix modification technique. The stabilization and the pyrolysis temperatures for germanium were investigated with various chemical modifiers including palladium, palladium–magnesium, palladium–strontium and palladium–zirconium. The highest pyrolysis temperature and highest integrated absorbance were obtained using palladium–zirconium modifier, and the severe matrix interference from sulfate can be eliminated. The characteristic mass and absolute detection limit (3σ) of germanium were found to be 16 and 12 pg, respectively. The proposed method was applied to the determination of trace levels of germanium in botanical samples with a recovery range of 92–106%. The hydride generation atomic fluorescence spectrometric (HGAFS) method was employed to analyze the samples and the results agree well with those obtained by GFAAS. The contents of germanium in standard reference materials were determined and the results were in good agreement with the reference values.     

Determination of germanium by AAS in chloride-containing matrices

Interference effects of NaCl on the ET-AAS determination of Ge have been studied. The use of several matrix modifiers to alleviate this problem such as Ni and Zn perchlorates and nitrates, nitric acid, ammonium nitrate are reported. The stabilizing effect of Zn and Ni perchlorates allows the use of high pretreatment temperatures. NaCl is thus thermally volatilized from the atomizer by employing pretreatment temperatures higher than 1500 degrees C resulting in an improved sensitivity. Germanium levels in zinc plant slag samples, have been determined and compared to those obtained for the same samples spiked with NaCl with platform and wall atomization using nickel perchlorate as a matrix modifier. The results were compared with those from a hydride generation system equipped with a liquid nitrogen trap. The recoveries for germanium have been almost complete and amount to 99% for the original slag samples and 80% for 15% (w/w) NaCl containing spiked samples.     

Direct determination of parts-per-billion levels of germanium in botanical samples and coal fly ash by graphite furnace atomic absorption spectrometry

 Parts-per-billion levels of germanium can be determined directly by graphite furnace atomic absorption spectrometry (GFAAS) using palladium plus strontium as a mixed modifier resulting in pyrolysis temperatures up to 1400 °C without loss of germanium. At this temperature the matrix effect including the most troublesome sulfate interference can be eliminated. Palladium plus strontium nitrate is advantageous compared to palladium alone or palladium plus magnesium nitrate; an amount of 15 μg of sulfate does not show any interference on the determination of 1 ng of germanium. The method was successfully applied to the determination of ng/g levels of germanium in botanical samples and coal fly ash after thermal decomposition of the samples in a mixture of acids using a pressure bomb. The results were consistent with the reference values given for botanical samples and coal fly ash with a recovery range of 96.4∼103.4% Received: 16 September 1996/Revised: 10 December 1996/Accepted: 14 January 1997     

Determination of germanium by AAS in chloride-containing matrices

Interference effects of NaCl on the ET-AAS determination of Ge have been studied. The use of several matrix modifiers to alleviate this problem such as Ni and Zn perchlorates and nitrates, nitric acid, ammonium nitrate are reported. The stabilizing effect of Zn and Ni perchlorates allows the use of high pretreatment temperatures. NaCl is thus thermally volatilized from the atomizer by employing pretreatment temperatures higher than 1500°C resulting in an improved sensitivity. Germanium levels in zinc plant slag samples, have been determined and compared to those obtained for the same samples spiked with NaCl with platform and wall atomization using nickel perchlorate as a matrix modifier. The results were compared with those from a hydride generation system equipped with a liquid nitrogen trap. The recoveries for germanium have been almost complete and amount to 99% for the original slag samples and 80% for 15% (w/w) NaCl containing spiked samples.     

Germanium speciation by LC-HG-ICP/OES

Liquid chromatography-hydride generation-inductively coupled plasma optical emission spectroscopy (LC-HG-ICP/OES) has been used to determine inorganic and organometallic species of germanium. In recent studies these coupled systems has been applied successfully to the speciation of arsenic. To establish separation conditions for germanium two reversed stationary phases and different solvent mixtures for elution, in isocratic or gradient mode have been tested. The reduction of germanium species to the corresponding volatile hydride is a critical step, especially for acidity control, thus the conditions for reduction using different concentrations of acid have been studied systematically. For the conditions established quality parameters as limit of detection (at the g l^–1 level), precision and recovery have been determined for the germanium species considered in a saline matrix.