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1.
火焰原子吸收法测定有机锗(Ge-132)中的锗,线性浓度范围为0-1.25mg/mL,方法精度为1.2%,相对标准偏差〉2%,平均回收率为99.5%,杂质Pb和As用塞曼石墨炉原子吸收测定,Pb用(NH4)2HPO4+Mg作改进剂,As用Pd作改进剂,特征质量分别为8.2pg和8pg,相对标准偏差分别为2.1%和2.2%,并讨论了有关机理问题。  相似文献   

2.
石墨炉原子吸收法测定饮料和中成药中锗   总被引:4,自引:0,他引:4  
本文研究了石墨炉原子吸收(GFAAS)直接测定某些饮料和中成药中的锗。选用钯和酒石酸为改进剂与纯钯比较,灰化温度提高至1600℃未见锗的损失,灵敏度提高了37%。具有较强的抗干扰的能力。本法特征质量mo值为32pg,实际样品测定检出限为0.24μg/L(3σ计),相对标准偏差为2.6%,回收率89%-110%。  相似文献   

3.
氢化—AFS法测定青藏高原中草药中的微量砷,锑,硒和汞   总被引:24,自引:0,他引:24  
本文研究了氢化物发生无色散原子荧光法测定青藏高原中草药中的微量砷,锑,硒和汞的方法,在选定的最佳工作条件下,14种干扰元素的含量低于允许存在量,不影响测定,检出限(μg/mL)为:As1.3,Sb0.39,Se0.24,Hg0.44,9次测定的相对标准偏差(%)的为As2.4~4.2Sb2.5~5.6,Se3.1~5.0,Hg3.8~5.9。4个元素的回收率为94.7~105.4%本方法简便,快速  相似文献   

4.
火焰原子吸收法测定有机锗(Ge.132)①中的锗,线性浓度范围为0-1.25mg/mL,方法精度为1.2%,相对标准偏差<2%,平均回收率为99.5%。杂质Pb和As用塞曼石墨炉原子吸收测定,Pb用(NH_4)_2HPO_4+Mg作改进剂,As用Pd作改进剂,特征质量分别为8.2pg和8pg,相对标准偏差分别为2.1%和2.2%,并讨论了有关机理问题。  相似文献   

5.
李宝军  李国正  刘恩科 《光学学报》1997,17(12):1718-1723
对1.55μm波长的Si1-xGex光波导和Si1-xGex/Si多量子阱(MQW)红外探测器的集成器件结构进行了系统的分析和优化设计。优化结果为:1)对Si1-xGex光波导,Ge含量x=0.05,脊宽、高和腐蚀深度分别为8、3和2.6μm;2)对Si1-xGex/Si多量子阱红外探测器,Ge含量x=0.5,探测器由厚度为550nm、23个周期的6nmSi0.5Ge0.5+17nmSi组成,长度约2mm。结果表明,这种结构器件的内量子效率可达88%。  相似文献   

6.
等色染料离子对浮选光度法测定铂   总被引:5,自引:1,他引:4  
提出了等色染料离子对浮选光度法、向罗丹明6G(R6G)和Pt(SnCl3)5^3-的异丙醚浮选物Pt(SnCl3(5(R6G)3中,加入PH=5.5的醋酸-醋酸铵缓冲溶液,使R6G离子进入水相,并向其中加入与R6G颜色相同的四溴荧光素(TBF)〉形成等色染料等离子对R6G,TBF,再被甲茉浮选,将浮选物溶于丙酮,于530nm处进行光度测定,由于6个染料分子(Pt:R6G:TBF)=(1:3:3)e  相似文献   

7.
间接光度法测定天然水中痕量Se(Ⅳ)   总被引:1,自引:0,他引:1  
本文提出了在表面活性剂TPC存在下,I3^-间接光度法测定痕量硒。该方法灵敏度高,除铁外其他离子基本无干扰,选择性好,测定2.0μg Se(Ⅳ)的样品10次,RSD=3.9%,精密度较好,适用于水样中Se(Ⅳ)的测定,实测了天然水中硒,结果满意。  相似文献   

8.
李宝军  李国正 《光学学报》1997,17(12):718-1723
对1。55μm波长的Si1-xGex光波导和Si1-xGex/Si多量子阱红外探测器的集成器件结构进行了系统的分析和优化设计。优化结果为:1)对Si1-xGex光波导,Ge含量x=0.05,脊宽,高和腐蚀深度分别为8,3和2.6μm,2)对SI1-xGex/Si多量子阱红外探测器,Ge含量x=0.5,探测器由厚度为550nm,23个周期的6nmSi0.5GE0.5+18nmSi组成,长度约2mm。  相似文献   

9.
锡,锗化合物的光电子能谱和质谱研究   总被引:1,自引:0,他引:1  
用光电子能谱(XPS)和质谱(MS)分别研究了9种锗,锡的化合物Ge3d,Sn3d轨道电子结合能化学位移与其所处不同化学环境的关系。着重讨论了取代基团电负性对Ge3d,Sn3d结合能化学位移的影响。  相似文献   

10.
等离子体发射光谱法测定富硒鸡蛋中的营养元素   总被引:2,自引:0,他引:2  
赵爱东 《光谱实验室》2000,17(2):226-228
本文利用高频电感耦合等离子体光谱仪直接测定了富硒鸡蛋中的Fe,Zn,Ca,Mg,Mn,Se和Cu7种微量元素,方法简便,快速,可靠,具有良好的精密度和准确度。相对标准偏差为1.5% ̄6.7%,回收率为93% ̄106%,测定结果令人满意。  相似文献   

11.
石墨炉原子吸收法测定人红细胞膜结合硒   总被引:1,自引:0,他引:1  
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。  相似文献   

12.
Mass excesses of short-lived A=2Z-1 nuclei (63)Ge, (65)As, (67)Se, and (71)Kr have been directly measured to be -46,921(37), -46,937(85), -46,580(67), and -46,320(141) keV, respectively. The deduced proton separation energy of -90(85) keV for (65)As shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of (65)As suggest that the majority of the reaction flow passes through (64)Ge via proton capture, indicating that (64)Ge is not a significant rp-process waiting point.  相似文献   

13.
利用红外非线性光学晶体材料对已有的成熟的激光光源进行频率转换是获得3~5μm和8~12μm"大气窗口"红外激光的主要方法。传统的红外非线性光学晶体存在缺陷,不能满足应用要求,需要探索新型的红外材料。综述了以硫族化合物为研究对象,寻找新型中红外非线性光学晶体材料的研究进展。介绍了Li MQ2(M=Ga,In;Q=S,Se,Te),BaGa4S7,BaGa4Se7,BaGa2MQ6(M=Si,Ge;Q=S,Se)及Li2In2MQ6(M=Si,Ge;Q=S,Se)的研究进展。  相似文献   

14.
将具有负宇称的 fp 空间扩大到包含1g9/2 轨道, 采用修正的表面相互作用(MSDI), 对64Ge, 66Ge, 68Ge, 70Se, 72Se, 74Se, 76Kr 和 78Kr等偶偶核作了形变Hartree Fock计算, 得到了基态和一些激发态的解. 同时, 还用近似角动量投影形变Hartree Fock(PDHF)方法对偶偶核64Ge, 74Se和奇A核79Kr进行了能谱计算, 得到其正、 负宇称带的解, 计算结果与实验谱基本一致.Using modified surface delta interaction, enlarging the fp configuration space to include the 1g9/2 orbit with the abnormal parity, the deformed Hartree Fock calculations for the eight nuclei: 64Ge, 66Ge, 68Ge, 70Se, 72Se , 74Se, 76Kr and 78Kr are performed. The ground state and some particle hole excited configurations are obtained. The approximate angular momentum projected deformed Hartree Fock (PDHF) method is applied to even even nuclei 64Ge and 74Se and odd A nuclus 79Kr. Both of their normal and abnormal parity bands are obtained. The calculated energy spectra are consistent well with experimental spectra.  相似文献   

15.
The full set of partial structure factors for the prototypical network glass GeSe2 was measured using the method of isotopic substitution in neutron diffraction. The basic building block of the network is the Ge(Se(1/2))(4) tetrahedron in which 34(5)% of the Ge reside in edge-sharing configurations. The intrinsic chemical order of the glass is, however, broken with a maximum of 25(5)% Ge and 20(5)% Se being involved in homopolar bonds at distances of 2.42(2) and 2.32(2) A, respectively.  相似文献   

16.
在烟草中的有机和生物活性成分被鉴定出来之后,分析和鉴别其中的无机元素就变得非常重要。采用电感耦合等离子体质谱法同时测定了烟叶中Be,Na,Mg,K,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Sr,Mo,Ag,Cd,Sn,Cs,Ba,Hg,Tl,Pb,Th和U共27种元素。样品的前处理采用硝酸和过氧化氢混合溶液。通过在线加入内标液的方法来校正由于基体效应和信号漂移对测量所造成的影响,内标选用锗、铟和铋3种元素。方法的回收率为93.64%~108.9%,检出限为0.356 3 ng·L-1~1.725 μg·L-1,相对标准偏差1.28%~9.18%。实验结果表明该方法能满足痕量分析的要求。  相似文献   

17.
The temperature dependence of the dc conductivity and thermoelectric power was determined for five different amorphous chalcogenide Se–Ge–Te films, with Ge?=?3.0–22?at.%, Se?=?0–97?at.% and Te?=?0–97?at.%. The films were prepared by thermal evaporation of GeSe4, GeTe4 and GeSe2Te2 quenched bulk materials. Values of the activation energy calculated from the temperature dependence of both electrical conductivity and thermoelectric power showed a decrease with increasing Ge content in the Se–Ge films as well as with replacement of Te for Se in the Se–Ge–Te films. The results showed an Anderson transition, with the conductivity showing insulating behaviour on the Ge–Se side to metallic behaviour at the binary composition Ge–Te. The radius of localization was obtained for the different compositions investigated. The wave function associated with the charge carriers at the composition Ge3.3Te96.7 is non-localized. A minimum metallic conductivity of 237?±?5?(Ω?cm)?1 was found.  相似文献   

18.
Semiconductor germanium (Ge) in contact with some metals, such as Al, Pd, and Au, etc., is a class of distinctive materials with non-integer dimensions (D) that differ from integer dimensional materials, such as nanoparticles (0D), nanowires/nanorods//nanotubes/nanoribbons (1D), and thin films (2D). In this article, we describe our efforts toward understanding the annealing strategies and perspectives of metal-induced crystallization for the amorphous Ge embedded in Al, Pd, and Au matrices prepared by high vacuum thermal evaporation techniques, highlighting contributions from our laboratory. First, we present the Al-induced crystallization of amorphous Ge and formation processes of fractal Ge patterns. In addition, the fractal Ge patterns induced by Pd nanoparticles with solid-state reactions will be summarized in detail. Temperature-dependent properties of resistance and fractal dimension in Pd/Ge bilayer films will be expounded. In particular, the nonlinear optical properties are discussed in detail. Finally, we will emphasize the in situ observations by transmission electron microscopy and multi-fractal analysis for the fractal Ge patterns induced by Au nanoparticles. Moreover, the polycondensation-type fractal Ge patterns with non-integer dimensions, thick branches and smooth edges, and metastable gamma-Au0.6Ge0.4 are further investigated. The computer simulation indicated that the experimental results are good agreement with the simulation patterns, which were carried out by a ripening mechanism of non uniform grains. This review may provide a novel insight to modulate their competent performance and promote rational design of micro/nanodevices.  相似文献   

19.
本文研究了用 ICP- AES法测定 Pd/Al2 O3催化剂中钯所存在的干扰问题。考察了基体及所用试剂对钯测定的影响 ,发现氧化铝基体、硫酸等对钯的测定均有负干扰 ,提出采用基体匹配法测定 Pd/Al2 O3中的钯含量。方法回收率在 96%以上 ,9次测定相对标准偏差小于 3%  相似文献   

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