电感耦合等离子体质谱法研究黄河甘宁蒙段附近居民砷暴露水平（英文）

人类砷暴露可以通过空气、饮用水和食物等途径。运用ICP-MS方法分析了四个采样点河曲(Hequ,HQ)、石嘴山(Shizuishan,SZS)、中卫(Zhongwei,ZW)和临夏(Linxia,LX)的69份当地居民发样及四个黄河过滤水样的总砷含量,探究了头发中砷水平在不同性别及年龄中的差异,并对发样中砷与水样中砷的相关性进行了分析。人发样品采用微波消解方法进行前处理,消解效果良好。结果表明,该方法准确度及精密度良好,回收率为90.1%~101.9%,RSD值为2.9%~4.2%。结果显示,该研究地区居民发样砷含量范围为0.01~1.73μg·g-1,平均值为0.33μg·g-1,不同采样点的砷含量顺序为ZWHQLXSZS。Kruskal Wallis检验显示该文中不同采样点发样砷含量存在显著性差异(p=0.010),说明研究地区的生活区域对居民发样砷含量具有影响,而不同性别(p=0.158)和不同年龄(p=0.159)组居民发样砷含量无明显差异,但男性发砷平均值含量高于女性,不同年龄组间呈现发样砷含量随年龄增大而下降的趋势。与文献相比,该研究发样砷含量较高于多数地区而明显低于地方性砷中毒区域。黄河水样中砷含量范围为2.31~10.41μg·L-1。与黄河下游等地区相比砷含量较高,但未超出地表水环境Ⅲ类标准。Pearson相关性系数表明,水中砷元素与铅、铜、铬、镉等元素均具有相关性,与人发砷含量具有显著正相关。总之,采样点附近居民具有较高砷暴露风险,且该风险可能来自于工农业排放。研究结果为甘宁蒙等西北民族地区重金属污染研究提供实验数据和理论依据。     

电感耦合等离子体质谱法研究黄河甘宁蒙段附近居民砷暴露水平

人类砷暴露可以通过空气、饮用水和食物等途径.运用ICP-MS方法分析了四个采样点河曲(Hequ,HQ)、石嘴山(Shizuishan,SZS)、中卫(Zhongwei,ZW)和临夏(Linxia,LX)的69份当地居民发样及四个黄河过滤水样的总砷含量,探究了头发中砷水平在不同性别及年龄中的差异,并对发样中砷与水样中砷的相关性进行了分析.人发样品采用微波消解方法进行前处理,消解效果良好.结果表明,该方法准确度及精密度良好,回收率为90.1%~101.9%,RSD值为2.9%~4.2%.结果显示,该研究地区居民发样砷含量范围为0.01~1.73 μg·g-1,平均值为0.33 μg·g-1,不同采样点的砷含量顺序为ZW>HQ>LX>SZS.Kruskal Wallis检验显示该文中不同采样点发样砷含量存在显著性差异(p=0.010),说明研究地区的生活区域对居民发样砷含量具有影响,而不同性别(p=0.158)和不同年龄(p=0.159)组居民发样砷含量无明显差异,但男性发砷平均值含量高于女性,不同年龄组间呈现发样砷含量随年龄增大而下降的趋势.与文献相比,该研究发样砷含量较高于多数地区而明显低于地方性砷中毒区域.黄河水样中砷含量范围为2.31~10.41 μg·L-1.与黄河下游等地区相比砷含量较高,但未超出地表水环境Ⅲ类标准.Pearson相关性系数表明,水中砷元素与铅、铜、铬、镉等元素均具有相关性,与人发砷含量具有显著正相关.总之,采样点附近居民具有较高砷暴露风险,且该风险可能来自于工农业排放.研究结果为甘宁蒙等西北民族地区重金属污染研究提供实验数据和理论依据.     

流动注射-氢化物发生-气相化学发光法测定环境样品中的总砷

采用流动注射-氢化物发生-气相化学发光法,建立了一种快速简便测定环境样品中微量砷的新方法。土壤样品、地表水样经消解后,加入抗坏血酸和硫脲,将5价砷还原为3价后,以0.6mol/L硫酸为载液,与1.5%硼氢化钠反应,生成的胂化氢由气液分离器分离后,在反应室里与臭氧反应,产生的化学发光信号由光电倍增管检测。该法线性范围宽(1—500μg/L),检出限为0.15μg/L,相对标准偏差为0.77%(20μg/L,n=11),采样速度为50样/h。应用于环境样品中总砷的测定,结果与氢化物发生原子吸收法一致。     

氢化物-原子吸收光谱法测定地球化学样品中的砷、锑、铋

氢化物-原子吸收光谱法是测定砷、锑、铋等元素的一种快速、灵敏、准确的方法,国内外已有不少报导。但是对共存元素的干扰研究较少,难于直接用于组成复杂的地质样品分析。为了适应大批地球化学样品中砷、锑、铋的分析,本文较详细地研究了用氢化物-原子吸收光谱法在同一份溶液中连续测定砷、锑、铋的仪器工作条件、氢化物发生条件及共存元素的干扰。选出了对砷、锑、铋均为有效的还原抑制剂。在选定的条     

流动注射在线富集火焰原子吸收测定痕量砷

本文在比较各种柱材料对砷的富集效果的基础上，选用活性氧化铝作柱材料的进行在线富集流动注射火焰原子吸收测定砷的研究。实验溶液含砷１．２５μｇ／ｍｌ，ＰＨ＝６，当流速为１６ｍｌ／ｍｉｎ时，富集倍数为进样１分钟富集４８倍；当峰高为０．１吸光度时，宽仅为１．５秒。该方法用于环境水样中砷一的测定，结果较满意。     

共价氢化物与汞离子反应的研究：Ⅳ.痕量砷高灵敏度的分析方法

本文提出了一个氢化物发生－冷原子荧光法间接测定痕量砷的新方法。考察各种实验条件，并将此法用于水及饮料中痕量砷的分析，结果令人满意，对水中痕量砷检出限为０．５μｇ／Ｌ，回收率９４．７－１０３％。     

原子荧光光谱法测定中药材中砷的不确定度评定

建立氢化物发生-原子荧光光谱法测定中药材中砷含量的不确定度评定的方法,为评价测量结果提供科学依据。检测结果的不确定度由标准物质、标准溶液的配制、校准曲线的拟合、样品定容体积、样品称样量、测量重复性及回收率等所引入的不确定度分量组成。对合成不确定度进行计算,当中药材中砷含量为0.340mg/kg时,扩展不确定度为0.012mg/kg(k=2)。     

HPLC-ICP-MS联用技术研究甲醇对砷形态分析结果的影响

砷是一种有毒并致癌的化学元素，普遍存在于各种环境介质和生物体中。研究表明，砷对生物体的毒性不仅与砷的浓度，还和其存在形态密切相关。因此，对砷的不同形态进行分析具有重要意义。以往的研究表明，甲醇被广泛用作固体样品砷形态分析的提取剂，一定量的甲醇可以提高ICP-MS测总砷的信号强度。但是，关于甲醇对砷形态分析结果的影响研究尚未见报道。应用高效液相色谱-电感耦合等离子体质谱联用技术(HPLC-ICP-MS)建立同时测定AsC，AsB，As(Ⅲ)，DMA，MMA和As(Ⅴ)等六种砷形态的优化方法。HPLC采用阴离子交换柱，30 mmol·L-1 (NH₄)₂CO₃(pH=9.3)作为流动相。选择DRC模式，以O₂为反应气体，监测91AsO+作为检测信号。方法学验证表明，六种砷形态的线性相关系数都大于0.998 9。采用不同浓度的甲醇(0～100%)作为砷形态定容溶液，发现随着甲醇浓度的增加，As(Ⅲ)和DMA的峰面积显著增加。选取对砷形态结果影响最小的25%甲醇-水作为定容溶液时，其对不同浓度的砷均有一定的影响，并且对As(Ⅲ)和DMA影响最大。因此，在今后的研究中，甲醇的去除起着重要的作用。     

悬浮进样-氢化物发生-原子吸收光谱法测定化妆品中的微量砷

建立了一种悬浮进样-流动注射-氢化物发生-原子吸收光谱测定化妆品中痕量砷的新方法,实验考察和优化了影响砷信号强度的氢化物发生条件和悬浮条件.以无水乙醇作分散剂,1.5g/L琼脂作稳定剂,得到了满意的分析效果.方法具有操作简易、快速,灵敏度高等特点.     

X射线荧光光谱快速分析地质物料主、次元素

本文建立了X射线荧光光谱分析地质、化探扫面样的快速方法，掌握各元素的分析特征，选择适宜的条件，从而缩短分析时间，降低其成本，达到快速、简便的目的。     

磷砷化镓黄色发光二极管

采用掺氨砷压法在磷化镓衬底上外延生长掺碲n型的GaAs0.15P0.85:N/GaP材料,制成磷砷化镓黄色发光二极管,测量了其光学和电学性能.讨论了影响器件发光效率的因素.     

砷和汞的顺序注射-蒸气发生原子吸收光谱测定

本文建立了砷和汞的顺序注射 蒸气发生原子吸收光谱测定方法。在流动注射蒸气发生原子吸收光谱测定方法的基础上 ,采用汇流技术 ,通过两个微量注射泵和一个多位选择阀的计算机程控操作 ,实现待测组分与硼氢化钠间的强氧化还原反应及其气 液分离过程。与流动注射方法相比 ,进一步大幅度节省试剂消耗 ,显著提高分析的精度及长期稳定性。在 1 2 0·h- 1 的采样频率下汞和砷的测定精度RSD分别为 2 2 %和 1 4%,检出限分别为 0 1 5和 0 0 7μg·L- 1 。方法用于地球化学标准样品的分析 ,取得满意结果。     

The specific heat of bulk amorphous arsenic

The specific heat of bulk amorphous arsenic deposited from the vapor at 415°K has been measured between 1.8 and 20°K. A comparison with compacted amorphous As films deposited at room temperature reveals appreciable differences in the form of C/T³. The results indicate a relative increase in the density of low frequency vibrational modes in the bulk amorphous As. The specific heat measurements support x-ray and Raman scattering studies that suggest variations in the local structure of amorphous As prepared under different deposition conditions. A comparison with neutron scattering measurements in bulk amorphous As also indicates an underestimate of the low frequency density of states.     

Investigation of the perfection of diffusion layers obtained in the diffusion of zinc in gallium arsenide

The degree of perfection of diffusion layers in gallium arsenide was investigated experimentally in relation to the surface concentration of zinc, the arsenic vapor pressure, the diffusion temperature, and the cooling conditions of the specimens after diffusion. By optical microscopy and X-ray diffraction it was shown that diffusion layers of gallium arsenide can be very strongly disrupted during the diffusion of zinc, and their structure may frequently approach that of mosaic crystals. This disruption is caused mainly by dislocations, which may exceed 10⁷/cm² in density. The disruptions are lower with lower surface concentration of zinc, with high arsenic vapor pressures (1.5 atm) compared with the normal, and with lower diffusion temperatures.The authors wish to convey their gratitude to V. A. Presnov and M. P. Yakubene for discussing the results and taking an interest in the work     

Effect of the Arsenic Concentration on the Characteristics of the Growth Step Echelon in GaAs Epitaxy

The effect of the arsenic concentration in the vapor phase on the growth step distribution over the surface of GaAs epitaxial layers grown in a chlorine-hydride vapor-transport system on substrates with 4° (111)A and (113)A orientations is studied. It is demonstrated that the average distance between steps in the echelon depends on the arsenic concentration and increases with it up to a certain constant value. It is assumed that this is connected with the change in the kink density at the steps.     

Synthesis of an innovative calcium-alginate magnetic sorbent for removal of multiple contaminants

A new calcium-alginate magnetic sorbent has been prepared by an electrostatic extrusion technique. The sorbent has the calcium alginate as a bio-polymeric shell and iron oxides as magnetic cores. It is characterized by a multifunctional property: ease in separation via magnetic force, and effective adsorption of arsenic(V) and copper ions. It has been found that the equilibrium time of copper and arsenic(V) can be attained in less than 3 and 25 h, respectively. The maximum adsorption capacities of arsenic and copper ions are 6.75 and 60.24 mg/g, respectively, which are much higher than those of commercial adsorbents. Solution pH plays a key role in adsorption. The adsorption of arsenic increases as the pH is decreased. On the other hand, higher pH can enhance adsorption of copper ions.     

Quantitative Auger analysis of ion-implanted boron and arsenic in polycrystalline silicon

Quantitative analysis of boron and arsenic in silicon has been made by Auger electron spectroscopy with the in-situ ion milling technique. Ion-implanted boron and arsenic in polycrystalline silicon was used as standard samples. The experimental results indicate that the semi-empirical formalism for quantitative Auger analysis is valid for impurity concentrations less than a few percent. Excellent linear relationship has been obtained between the implanted dose and the normalized Auger signal intensity within ±10% for boron and ±20% for arsenic in silicon.     

Catalyst-free growth of well-aligned arsenic-doped ZnO nanowires by chemical vapor deposition method

ZnO nanowires with different arsenic concentration were grown on Si (1 0 0) substrates by chemical vapor deposition method without using catalyst. Zn/GaAs mixed powders were used as Zn and As source, respectively. Oxygen was used as oxidant. The images of scanning electron microscope show that the arsenic-doped ZnO nanowires with preferred c-axial orientation were obtained, which is in well accordance with the X-ray diffraction analysis. The arsenic related acceptor emission was observed in the photoluminescence spectra at 11 K for all arsenic-doped ZnO samples. This method for the preparation of arsenic-doped ZnO nanowires may open the way to realize the ZnO nanowires based light-emitting diode and laser diode.     

吖啶橙-罗丹明B荧光共振能量转移猝灭法测定砷

研究了利用吖啶橙(AO)-罗丹明B(RB)共振能量转移荧光猝灭法测定痕量砷的方法。在λ_ex/λ_em=470/580 nm,0.016 mol·L-1 H₂SO₄溶液中,十二烷基苯磺酸钠(DBS)存在下,吖啶橙-罗丹明B能够发生有效的能量转移,使罗丹明B的荧光强度大大增强;在酸性条件下,砷与钼酸铵生成砷钼杂多酸使能量转移体系罗丹明B的荧光猝灭。利用吖啶橙-罗丹明B能量转移荧光猝灭法测定痕量砷,砷在0.01～0.25 mg·L-1范围内与罗丹明B荧光猝灭程度呈良好的线形关系,方法检出限为2.56 μg·L-1。该方法用于茶叶中痕量砷的测定,相对标准偏差为0.48%～0.64%,回收率为98%～103%,结果满意。