ICP-AES法测定蒿甲醚中 Cu、Pb、Zn、As、Sb和Cd

本文有用硝酸－高氯酸消解蒿甲醚样品，ICP－AES法同时测定其中痕量的Cu、Pb、Zn、As、Sb和Cd等。研究了样品处理方法及高氯酸残余量对测定的干扰，选择了仪器最佳工作条件，考查了方法准确度和精密度，6种元素加标回收率在91％－110％范围内，RSD（n=7)为4．2％－6．5％。     

氢化物－原子荧光法快速测定含金化探样品中硒

王水分解样品，Ｆｅ３＋作减缓剂。对比了不同酸度的王水和ＨＣｌ介质中Ｓｅ的相对荧光强度。在选择的酸介质条件下，研究了不同量的Ｆｅ３＋以及干扰元素对Ｓｅ荧光强度的影响和Ｆｅ３＋抑制干扰的效果。确定了Ｆｅ３＋存在下，Ａｕ／Ｓｅ的干扰限。样品中加入硒标准回收率在９０％－１０３％，用于８个地球化学标样分析，结果满意。方法检出限为０．０５×１０－６。     

用巯基乙酸作稳定剂制备CdSe纳米晶的光学性质

以巯基乙酸为稳定剂制备了CdSe纳米晶，通过尺寸选择沉淀得到2nm到3nm之间不同尺寸的纳米晶，利用室温光吸收，光致发光（PL）和光致发光激发（PLE）谱来研究了CdSe纳米团簇的光学性质。紫外－可见吸收谱给了具有清晰激光特征的尖锐吸收边，这表明样品的尺寸分布很窄。光致发光研究表明，样品有两个发射带，一个具有较高能量位于吸收边，来自电子－空穴对从最低激发态能级弛豫后的辐射复合，另一个低能发射带归属于基质与纳米晶界面存在的俘获中心。PLE谱中有2个吸收带，分别是S－S和P－P跃迁。最后还给出了不同激发能量下的发光特性。     

波长色散X射线荧光光谱法测定黄金饰品含金量

本文提出应用波长色散Ｘ射线荧光光谱仪测定黄金饰品含金量的方法，本法对原有样品盒进行了改造，增设特制窗口和采取样品固定等措施，以系列参考标样建立校准曲线，用经验系数法校正基体效应。比例模拟法校正含量。９个参考标样和１６个金标牌的测定结果表明，在含金量为３７．５０％－９９．９９％的范围内，方法的准确度好：含金量在９９．９９％－９８．９８％范围时，误差为０．０３％－０．１２％，在９８．９８％－３７．５０％范围时，误差为０．０１％－０．５２％，选用含金量不同的５个参考标样为代表，以０．７和１．４的模拟比例，经不同时间多次测定进行统计，相对标准偏差为０．０５％－０．５０％，说明方法的精密度好，本法操作方便，时样品无破坏     

光电直读光谱法测定稀土铝合金中La,Ce,Pr,Nd,Sm ,Si,Fe,Cu

本文报道了稀土铝合金中La,Ce,Pr,Nd,Sm,Si,Fe,Cu的光电直读光谱测定，对光源的激发方式及最佳工作条件进行了选择，应用KH－5高能预火花光源，采用单向全功率放电，先冲洗3秒，然后预燃5秒，曝光10秒。各元素谱线间无干扰，。使用固体试样，样品处理简单。经试验验证该法简便快速，精密度准确度高，含量在0．001％－0．002％之间RSD＜6％，0．02％－0．3％之间RSD＜3％，标准样品的测定值与准确值吻合较好，结果令人满意。     

石墨炉原子吸收法测定人红细胞膜结合硒

本文采用镍－硝酸镁作基体改进剂，用石墨炉原子地测定人红细胞膜结合硒，并对该方法进行了研究探索，在选定的实验条件下，该方法特征质量为１６．０ｐｇ／０．００４４Ａ．Ｓ，检出限为７．４ｐｇ，回收率为９２％－１０８％，相对标准偏差为８．９％，１０种共存元素含量在正常生理浓度范围内不干扰测定，经过样品测试分析，证明本方法准确，快速，满足分析要求。     

正三辛胺萃取－5－Br－PADAP－OP显色体系光度法测定铜

采用５－Ｂｒ－ＰＡＤＡＰ－ＯＰ显色体系测定铜，考查了测定条件。以正三辛胺萃取分离干扰高子，考查了萃取分离条中。人工合成样品回收率１００．８％，铝合金标样测定误差＜－２．２％，人发分析结果的相对标准偏差＜４．０％。     

小白鼠组织和骨中铜锌铁钙镁的测定

本实验利用原子吸收光谱法对小白鼠组织及骨中Ｃｕ，Ｚｎ，Ｆｅ，Ｃａ，Ｍｇ含量进行了测定。样品采用浓ＨＮＯ２和ＨＣｌＯ４湿法消化，并用国家计量局的猪肝（ＧＢＷ０８５５１）作为标准物对测定方法进行了考核，测定值与标准值吻合。方法加收率：Ｃｕ９９－１００％，Ｚｎ１０２－１０３％，Ｆｅ９９－１００％，Ｃａ９９－１０４％，Ｍｇ１０１－１０３％，ＣＶ值为１．７－３．９％。方法简便，快速，准确度高，需样量少，符合     

火焰原子吸收光谱法测定磁化杯中铅、镉和铁

本文研究了火焰原子吸收光谱法测定磁化杯陶瓷内胆中Ｐｈ、Ｃｄ和Ｆｅ含量的方法。样品经粉碎，用硝酸－高氯酸混合液进行消解后测定。本法灵敏度高，干扰少，简单，快速，具有良好的精密度和准确度，其相对标准偏差分别为Ｐｂ３．９９％，Ｃｄ１０．７％，Ｆｅ０．９％。回收率Ｐｂ１００．６１％，Ｃｄ１０１．１８％，Ｆｅ１０２．４％。     

原子吸收光谱法测定趾甲微量铁,钴,镍和镉

作者在十年内按季度收集了人趾甲样品３９份。应用火焰原子吸收光谱法测定了人趾甲样品的微量元素含量；此法具有良好的精密度和准确度，相对标准偏差为１．６９％－７．７１％，回收率在９１．３５％－１０４．７５％之间。用本法测定了人趾甲样品的微量铁、钴、镍和钢，获得了满意的结果。     

Phase transformation and quantum confinement effect in CdSe/Se multilayer thin films prepared by physical vapour deposition

CdSe/Se multilayer (ML) thin films with different thickness ratios of Se and CdSe sublayers were prepared by using a thermal evaporation method. Prepared samples were annealed at temperature 300 K. From X-ray diffraction (XRD) studies, samples prepared at room temperature showed a (100) plane of CdSe with wurtzite structure, whereas the annealed samples confirmed the cubic structure. Stress created in ML systems was calculated from XRD data and found that it increases with decreasing particle size. The energy band gap value of a CdSe/Se ML thin film is shifted to a value higher than that of the bulk CdSe (1.74 eV) semiconductor. This is due to decrease in the crystallite size smaller than the Bohr exciton diameter of CdSe (11.2 nm). Crystallite sizes (≈5 nm) were calculated from UV–VIS data with the predictions of an effective mass approximation model. The photoluminescence peak of the ML samples is split into two bands having nearest values due to the emissions from spin–orbit split-up of the excited energy state.     

CdSe epitaxial films and nanostructures grown by the isothermal closed space sublimation technique

The use of the isothermal closed space sublimation technique for growing CdSe very thin films and nanostructures is reported. In this technique, the samples are grown by exposing a substrate alternately to elemental sources of Cd and Se. The whole system is at the same temperature, so the only driving force for the film growth is the vapour pressure difference between the elemental source and the film surface. This is due to the difference in chemical potential between the pure elements and the elements when forming the compound. Between subsequent exposures the surface is exposed to the carrier vapour. In this step, re-evaporation of the non-stable outermost part of the films can be controlled. This procedure leads to a self-regulated growth rate in which the size of the deposited materials is controlled very accurately. In this way, nanostructures and epitaxial thin films of CdSe were grown on single-crystal substrates. For the nanostructure growth a nanoporous anodic alumina membrane (AAM) was interposed between the elemental sources and the substrate. Optical and structural properties of the structures are reported. The structural characterization using x-ray diffraction and high resolution electron microscopy reveals the epitaxial quality of the films and the chemical composition and morphology of the semiconductor filled AAM samples.     

水体中铬、镉和铅的X射线荧光光谱同时快速分析方法研究

以氢氧化钠和硫化钠为沉淀剂采用共沉淀法同时富集水体中的Cr,Cd和Pb,通过对Cr(OH)₃,Cd(OH)₂和PbS沉淀均匀悬浮液抽滤以制成Cr,Cd和Pb均匀分布的薄膜样品并进行能量色散XRF光谱测量,以实现水体中Cr,Cd和Pb的同时快速分析与检测。研究了富集过程中的反应时间和反应物摩尔比对薄膜样品XRF光谱强度的影响,确定了富集过程的最佳反应条件为沉淀反应时间为5 min,OH-与Cr3+的最佳摩尔比为5.0,OH-与Cd2+的最佳摩尔比为5.0,S2-与Pb2+的最佳摩尔比为2;对富集后不同浓度的薄膜样品进行了均匀性检验,富集区域6个不同位置荧光强度的相对标准偏差均小于4.8%,说明富集后的薄膜样品具有较好的均匀性;将不同浓度薄膜样品的理论浓度值与ICP-MS方法测得的浓度值进行对比分析,验证了该富集方法对水样中Cr,Cd和Pb的富集率均能达到90%以上;根据薄膜样品的荧光强度与ICP-MS测得的浓度值,建立了基于该富集方法的水体中Cr,Cd和Pb的X射线荧光光谱定量分析方法,Cr,Cd和Pb校准曲线的线性相关系数分别为0.997 3,0.995 0和0.999 8,当实际采集水样体积为50 mL时,Cr,Cd和Pb的检出限分别为7.4,29.6和8.5 μg·L-1,均低于《污水综合排放标准 GB 8978-1996》中Cr,Cd和Pb的最高允许排放浓度,因此该方法能够实现工业生产及生活排放污水中Cr,Cd和Pb的同时快速分析与检测。该研究为基于X射线荧光光谱法的水体多种重金属同时快速在线监测提供依据。     

An approach to MgCl2 activation on CdSe thin films for solar cells

The energy demand of the world is rapidly increasing and to cater this, there is a need to explore new renewable energy resources. CdSe thin film solar cells may be promising alternative to the CdTe solar cells which are extensively studied and used in solar cell technology. The pre/post deposition chlorine based treatments (viz. CdCl₂, MgCl₂, NH₄Cl) are the important steps to enhance the performance of Cd-based thin film solar cells. Therefore, a study on MgCl₂ activation treatment to CdSe thin films for solar cell applications as absorber layer is undertaken. Different physical properties of e-beam evaporated CdSe films (thickness 550 nm) grown on glass and ITO substrates are investigated and found to be strongly dependent on the post-chlorine treatment. The films have cubic zinc-blende structure and phase transformation from cubic (111) to hexagonal (002) is achieved with the MgCl₂ treatment while the optical band gap is reduced. I-V characteristics reveal the linear relation between voltage and current as well as the surface roughness is varied with treatment and improved homogeneity. The deposition of CdSe thin films is confirmed by elemental analysis where Cd and Se were found to be rich with treatment. The investigated results suggest that CdSe thin films treated by MgCl₂ and annealed at 320 °C may be a viable alternative absorber layer to the Cd-based solar cells.     

Solvothermal synthesis and characterization of CdSe nanocrystals with controllable phase and morphology

Zinc blende (ZB) CdSe hollow nanospheres were solvothermally synthesized from the reaction of Cd(NO₃)₂·4H₂O with a homogeneously secondary Se source, which was first prepared by dissolving Se powder in the mixture of ethanol and oleic acid at 205 °C. As Se power directly reacted with Cd(NO₃)₂·4H₂O in the above mixed solvents, wurtzite (W) CdSe solid nanoparticles were produced. Time-dependent experiments suggested that the formation of CdSe hollow nanospheres was attributed to an inside-out Ostwald ripening process. The influences of reaction time, temperature and ethanol/oleic acid volume ratio on the morphology, phase and size of the hollow nanospheres were also studied. Infrared (IR) spectroscopy investigations revealed that oleic acid with long alkene chains behaved as a reducing agent to reduce Se powder to Se²⁻ in the synthesis. Photoluminescence (PL) measurements showed that the ZB CdSe hollow nanospheres presented an obvious blue-shifted emission by 42 nm, and the W CdSe solid nanoparticles exhibited a band gap emission of bulk counterpart.     

Synthesis of Cadmium Selenide thin films at low-temperature by simple Chemical route and their Characterization

Crystalline CdSe thin film has been deposited using appropriate precursor solution containing cadmium sulfate octahydrate, tartaric acid, potassium hydroxide, ammonia and sodium selenosulfate. The effect of parameters such as bath composition, deposition temperature, pH of the solution, speed of the rotation and the specificity of complexing agent on growth process is studied. The ‘as-deposited’ CdSe thin film was found to be red in color, specularly reflective and well adherent to the glass substrate. The crystalline phase of the deposited sample was hexagonal wurtzite-type. The analysis of optical absorption data shows energy band gap energy (E_g) 2.01 eV. The morphological study and compositional analysis of film sample have been discussed. The electrical resistivity of CdSe thin film was found to the order of 10⁶ Ω cm.     

动态反应池电感耦合等离子体质谱法同时测定彩色卷烟纸中7种重金属

采用微波消解前处理样品,建立动态反应池电感耦合等离子体质谱法同时测定彩色卷烟纸中的Cr、Ni、As、Se、Cd、Hg和Pb7种重金属含量。该方法以钇(Y)作为内标补偿基体效应,采用动态反应池模式消除Cr、Ni、Se的质谱干扰,用茶叶标准物质对方法准确性进行校正。该方法相对标准偏差均小于10%、回收率为86.6%—120.9%、检出限为2.94—70.05ng/L,该方法操作简单、分析速度快、灵敏度高、准确度好,能快速、准确测定彩色卷烟纸中重金属。     

Nonstoichiometry of ZnSe and CdSe

The variation of the composition of CdSe and ZnSe with varying Cd, Zn or Se pressures at temperatures up to 1400 K was measured with an all-silica Bourdon gauge mounted in an autoclave. The results are evaluated in terms of nonstoichiometry. The metal excess is below detectability for ZnSe, but can be described with a $\text{1}\text{3}$ power dependence of the Cd pressure above CdSe, in reasonable quantitative agreement with literature data derived from Hall-effect measurements. Although excess selenium could also be found in both materials, this is interpreted as being a surface rather than a bulk effect.     

ICP-MS测定食用菌中硒的方法研究

采用石英高压消化罐在较低温度下缓慢消化食用菌样品,减少了硒的损失,以ICP-MS测定食用菌中微量硒,并对分析方法进行了研究。实验表明样品浓度、积分时间与响应值呈正相关。当样品中硒的浓度大于50 μg·L-1时,采用0.1 s的积分时间;硒的浓度小于5 μg·L-1时,采用高于2.0 s的积分时间。标准曲线在1.0～500 μg·L-1完成(r=1.000 0)。回收率为99.96%～102.7%。该法具有简便、快速、灵敏、稳定、准确等优点,用于食用菌中痕量硒的分析测定,结果令人满意。     

温控湿法消解ICP-MS测定全血中铅镉硒砷汞5种微量元素

采用温控HNO₃-H₂O₂湿法消解,ICP-MS测定全血中Pb, Cd, Se, As, Hg 5种微量元素的含量。在选定的测试条件下,仪器系统稳定性良好,Pb等5种元素的检出限范围2～40 ng·L-1,全过程中样品均重复测定3次,RSD均在3%内。采用国家全血溶液标准物质GBW(E)09034-09036和人发标准物质GBW09101b中的相应元素进行质量控制,检测结果和推荐值相吻合。同时,应用本方法实测了湘西汞矿区34名村民全血中的5种元素的含量,结果表明：矿区村民Se和As处于正常水平,血Pb、血Cd、血Hg含量均偏高,有较高的健康风险,应当引起有关部门的重视。本方法快速、灵敏,精密度及准确度均符合要求,适于人体全血样中Pb, Cd, Se, As, Hg等微量元素的测定。