电感耦合等离子体原子发射光谱法(ICP-AES)直接测定天然矿泉水中的硫酸根

建立了使用电感耦合等离子体原子发射光谱法(ICP-AES)直接测定天然矿泉水中硫酸根的方法,样品经过盐酸酸化,加热处理后直接上仪器测定。方法检出限达到0.05 mg/L,加标回收率达到95%~103%,重复性实验的相对标准偏差(RSD)低至1.0%,对比实验的相对偏差(RD)小于5%。     

氢化物发生原子荧光法测定天然矿泉水中的微量硒

测定硒含量的分析方法有许多 ,例如气相色谱法、比色法、荧光法、原子吸收分光光度法等。其中比色法缺陷较多 ,很少使用。其它几种方法各有优缺点 ,但都操作复杂、效率较低。用氢化物原子荧光光度法测定微量硒具有简便、快速、准确的特点 ,可以广泛应用于卫生检验。1　原理样品经酸消化后 ,在 6 mol/L盐酸介质中 ,将样品中的 6价硒还原为 4价硒 ,用硼氢化钾(KBH4)或硼氢化钠 (Na BH4)作还原剂 ,将 4价硒还原为硒化氢 (Se H4) ,由载气 (氩气 )带入原子化器中进行原子化 ,在特制硒空心阴极灯照射下 ,基态硒原子被激发至高能态 ,在去活化回…     

饮用天然矿泉水的锶限量指标

从锶对人体健康有益、锶的毒性很低、人类可能缺锶以及天然淡水锶含量考察等四个方面论述了提高我国饮用水锶限量指标的必要性,参考动物实验胚胎正常发育需要量、人类流行病学调查最佳饮水锶水平和临床安全剂量,建议将我国饮用天然矿泉水锶限量指标从5mg/L提高到10mg/L。     

GFAAS法测定天然饮用矿泉水中的钼

本文介绍了石墨炉原子吸收光谱法测定天然饮用矿泉水中的钼。水样不需浓缩萃取直接测定。线性范围０．０２～１．６ｎｇ，检测限０．０１ｎｇ，相对标准偏差２．３％－４．５％，回收率９６％－１０３％。     

CVG-ICP-AES法测定饮用天然矿泉水中痕量铅和汞

自制化学蒸气发生器并建立了KBrO3KBr K3Fe(CN)6HCl KBH4的CVG ICP AES同时直接测定饮用天然矿泉水中痕量铅和汞的方法,该方法提高了灵敏度,改善了检出限。方法的检出限分别为0.7μg·L-1(Pb220.353nm),0.1μg·L-1(Hg184.950nm),相对标准偏差分别为0.8%～7.8%(Pb)和0.5%～6.2%(Hg);回收率分别为90.0%～100.0%(Pb)和92.8%～108.0%(Hg)。方法完全能满足饮用天然矿泉水中痕量铅和汞的分析。     

黄龙山天然矿泉水临床应用观察

观察了黄龙山天然矿泉水系统治疗多种常见慢性病,如：消化功能紊乱,小儿厌食症,高血压病,神经衰弱、皮肤病等的效果,总有效率达92．58%,其原因是该矿泉水富含人体必需微量元素。     

心血管病患者饮用天然矿泉水的探讨

天然矿泉水是来自地下深处的泉水，水质清纯无污染，含有人体必需的微量元素。分析测定了来自不同地区的矿泉水样，对矿泉水中硅元素（硅酸含量）与钾、钠元素含量进行相关性研究，并从医学角度为心血管病患者饮用天然矿泉水提供依据。     

ICP-AES法测定钨矿中的钨

本文通过一系列的条件试验研究,确定了试样用HCl、HNO3、HF、H3PO4高温溶样,在碱性溶液中,用NaOH溶解钨,并使之与铜等杂质形成沉淀分离,在HCl介质中加入酒石酸,用电感耦合等离子体原子发射光谱法(AES-ICP)测定钨量,方法简便快速,准确可靠,测定范围宽,适用性广,用于钨矿中钨(0.040%~60.00%)的测定。其(n=6)相对标准偏差为(2.70%~0.13%),加标准回收率,钨在(97.80%~99.97%)之间。     

ICP-AES法直接测定氧化钇中的14个稀土元素

采用JY-38Ⅱ等离子光谱仪直接测定纯度99.5％～99.995％的氧化钇中的14个稀土杂质。试验考查了氧化钇基体、酸度、特别是共存元素的干扰影响,利用正交试验L_(16)(4~5)确定了仪器最佳条件。测定结果的相对标准偏差均小于5.0％,回收率在98.0％～108.0％之间。方法具有快速、简便及测定范围宽的特点,在实际应用中获得满意结果。     

ICP-AES法测定钢中的铈

建立了离子体发射光谱仪测定钢中铈元素的方法。为消除共存元素对铈分析游线的光谱干扰,选择Ce413．380nm作为分析线,铈含量在0．005％-0．50％之间工作曲线线性良好。对于含量范围在0．005％-0．10％的铈元素,回收率为85．6％-12．5％,测定结果的相对标准偏差小于9．74％（n=8）;对于含量范围在0．10％-0．50％的铈元素,回收率为99．5％-103．0％,测定结果的相对标准偏差小于3．52％（n=8）。该方法适宜钢中含量范围在O．005％-0．50％的铈元素的测定。     

EPR of vanadyl ion in a natural mineral, apophyllite

Single crystal EPR spectra of a natural mineral, apophyllite, containing VO(II) ion as an impurity have been investigated. The EPR spectra of the mineral, as obtained, was complex in nature, but was simplified by annealing the crystals at 490 K. The EPR parameters of the VO(II) species in the annealed crystal,g _∥ = 1.924 (2);g _⊥ = 1.983 (2);A _∥ = 18.35 (5); andA _⊥ = 7.24 (5)mT, are very close to a typical VO(II) impurity. Theoretically calculated line positions, using second-order hyperfine terms in the spin Hamiltonian with an axially symmetricg andA tensor values, agreed very well with the experimental ones. The EPR analysis of the annealed crystal has further revealed that the most preferred location of the VO(II) impurity is a substitutional Ca(II) site. The calculated bonding parameters and admixture coefficients indicate a fair amount of covalent bonding in the complex.     

High-precision direct determination of the Sr/Sr isotope ratio of bottled Sr-rich natural mineral drinking water using multiple collector inductively coupled plasma mass spectrometry

We describe a precise and accurate method for the direct determination of the ⁸⁷Sr/⁸⁶Sr isotope ratio of bottled Sr-rich natural mineral drinking water using multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The method is validated by the comparative analysis of the same water with and without cation-exchange resin purification. The work indicates that isobarically interfering elements can be corrected for when ⁸⁷Rb/⁸⁶Sr < 0.05 (Rb/Sr < 0.015), and that the matrix elements (Ca, Mg, K and Na) have no significant effect on the accuracy of the Sr isotope data. The method is simple, rapid, eliminates sample preparation time, and avoids potential contamination during complicated sample-preparation procedures. Therefore, the high sample throughput inherent to the MC-ICP-MS can be fully exploited.     

Simple collection and direct alpha-spectrometric determination of214Pb and214Bi in natural water

A rapid method has been developed for the de termination of²¹⁴Pb and²¹⁴Bi in natural waters by alpha-spectrometric measurement of²¹⁴Po. Well water was filtered on a membrane filter impregnated with manganese oxide and followed by direct alpha-spectrometric analysis. A prominent alpha peak was assigned to²¹⁴Po, which should be supported by the longer lived parents²¹⁴Pb and²¹⁴Bi. The activity ratios between²¹⁴Pb and²¹⁴Bi adsorbed on the filter were determined by using the change of activity of²¹⁴Po as a function of counting period after the filtration. The adsorbed yield of²¹⁴Pb was also determined from the growth of the alpha-peak due to²¹⁰Po from a²¹⁰Pb tracer added in the original water. The results indicated that the amount of²¹⁴Pb was in radioactive non-equilibrium state with the Rn-222 dissolved, while the activity ratios of²¹⁴Bi/²¹⁴Pb showed on increasing tendency with the storage period of the water.     

Speciation of aluminum in acidic natural water equilibria with mineral phase kaolinite by chemical equilibrium calculation

Aluminum is largely associated with aluminosilicate minerals such as kaoliniteAl,Si,Os(OH), within the earth's crustl. During the weathering, especially when the acidrain hastens the process, aluminum is released and thus becomes available tobiogeochemical processes. The elevated concentrations of aqueous aluminum causedetrimental consequences to plants, aquatic organisms and humans. Therefore, there havebeen considerable growing concerns in the aqueous chemistry of aluminum these years.'In …     

Adsorption of organic matter at mineral/water interfaces: 5. Effects of adsorbed natural organic matter analogues on mineral dissolution

The effects of the adsorption of pyromellitate, an analogue for natural organic matter, on the dissolution behavior of corundum (alpha-Al2O3) have been examined over a wide range of pyromellitate concentrations (0-2.5 mM) and pH conditions (2-10). The adsorption modes of pyromellitate on corundum have first been examined using in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and are shown to be dominated by a fully deprotonated, outer-sphere pyromellitate species ([triple bond]AlOH2+. . .Pyr4-) at pH >/= 5.0. At lower pH conditions, however, an additional protonated outer-sphere species ([triple bond]AlOH2+. . .H2Pyr2-) and an inner-sphere species are also evident. In accordance with the ATR-FTIR findings, modeling of macroscopic pyromellitate adsorption data using an extended constant capacitance treatment was possible using two outer-sphere ([triple bond]AlOH2+. . .Pyr4- and [triple bond]AlOH2+. . .H2Pyr2-) and one inner-sphere ([triple bond]AlPyr3-) adsorbed pyromellitate species. The presence of adsorbed pyromellitate strongly inhibited the dissolution of corundum under acidic (pH < 5) conditions, consistent with a mechanism previously proposed by Johnson et al. whereby outer-spherically adsorbed Pyr4- species sterically protect dissolution-active surface sites from attack by dissolution-promoting species such as protons. A reduction in the protolytic dissolution rate of corundum results. A reference Suwannee River fulvic acid, which also adsorbs to aluminum (oxyhydr)oxide surfaces in a predominantly outer-sphere manner, was similarly shown to strongly inhibit the dissolution of corundum at pH = 3.     

Natural radioactivity in bottled natural spring,mineral and therapeutic waters in Poland

Activities of ²³⁸U, ²³⁴U, ²²⁸Ra, ²²⁶Ra, and ²²⁴Ra as well as total α- and β-activities of 23 bottled spring, mineral and therapeutic waters produced and distributed in southern and central Poland are presented. The activities vary from a few tenth to a few mBq·L⁻¹ for uranium and to several hundred mBq·L⁻¹ for radium isotopes. The activities of ⁴⁰K were calculated from chemical analyses of potassium and checked for several mineral waters by gamma-spectrometer coupled with an HPGe detector. Positive correlation between water mineralization and activities of ⁴⁰K, ²²⁶Ra, as well as total alpha- and total beta-activities were observed. The radiological annual doses were calculated for all investigated waters and for different human age groups assuming the consumption of 1 liter of water per day. The calculated committed effective dose rate from uranium and radium isotopes resulting from consumption of the investigated waters exceeds the recommended value of 0.1 mSv per year in seventeen cases for infants and in one case for adults.     

Spectroscopic study of phase transitions in natural calcite mineral

The process and the formation of new minerals upon heating the carbonate rocks containing clay minerals, together with calcite are determined with thermal analysis, X-ray diffraction, infrared and Raman spectroscopy. The calcite-calcium oxide phase transition sequence was followed up to 947 degrees C in naturally occurring limestone samples. The spectral variations of the internal modes of the carbonate trigonal (nu(1), nu(2), nu(3) and nu(4)) were used to probe the structural phase transitions. The calcium oxide phase (which on reaction with atmospheric water forms portlandite) with an onset temperature of around 950 degrees C was also characterized by the appearance of the infrared mode around 450 cm(-1). The minerals, which were formed upon heating the calcite, were calcium oxide and wollastonite.     

The influence of kinetics on the direct titration curves of natural water systems — theoretical considerations

The effect of rate of complex formation is calculated on the titration curves of natural waters with traces of metals. The effect can be distinguished from multiple complex formation.     

A luminescence immunoassay test method for determining benzo[a]pyrene in natural water

A test method is developed for determining benzo[a]pyrene in natural water, based on the use of a polyethylene filter (frit) with adsorbed specific antibodies, placed within a transparent column. In passing a test solution, the analyte is adsorbed on the frit similarly to the process implemented in immunoaffinity preconcentration. The added conjugate of a labeled analyte takes the remained vacant binding sites of antibodies. Luminescent semiconductor nanoparticles (quantum dots) CdSe/ZnS, used as labels, enable visual determination under irradiation with UV light. The limit of detection for benzo[a]pyrene in water is ~0.5 ng/mL.     

Establishment of heterodinuclear replacement complexation and its application to direct determination of iron in natural water with dibromo-o-nitrophenylfluorone

The chromophore dibromo-o-nitrophenylfluorone (DBNPF) was used to complex Fe(III) and Cu(II) at pH 5.88. Fe(III) can competitively replace Cu(II) from its dinuclear complex Cu(DBNPF)Cu, and forms the Cu(DBNPF)Fe heterodinuclear complex. The Fe-DBNPF and Cu-DBNPF complexes were also characterized by the spectral correction technique. The heterodinuclear replacement complexation (HRC) is proposed and first used for the quantitative detection of iron in trace level with high sensitivity and good selectivity by the light-absorption ratio variation approach. The limit of detection of Fe is 1.0 μg L⁻¹. The method has been successfully applied to the direct determination of Fe(II, III) dissolved and bound to suspended substances in natural water.