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1.
偶合反应流动注射化学发光法测定汞   总被引:2,自引:0,他引:2  
基于Hg(Ⅱ)置换Fe(Ⅱ)-DETA配合物中的Fe(Ⅱ)和Fe(Ⅱ)-鲁米诺-溶解氧产生化学发光的反应,建立了置换偶合反应,流动注射化学发光测定痕量汞的新方法.方法线性范围为1×10~(-7)~1×10~(-5)g·ml~(-1)相对标准偏差为3.5%(n=11,C=1×10~(-6)g·ml~(-1)),检出限为3×10~(-8)g·ml~(-1),方法用于工业废水中汞的测定,结果令人满意.  相似文献   

2.
研究了四丁基溴化铵-硫氰酸铵-硫酸铵体系浮选分离铁(Ⅲ)的行为及与其他金属离子分离的条件.当四丁基溴化铵、硫氰酸铵和硫酸铵的浓度分别为8.0×10-4mol/L、6.0×10-3 mol/L和0.1 g/mL时,Fe(Ⅲ)可与Sn(Ⅳ),Cr(Ⅲ),Mn(Ⅱ),Al(Ⅲ),Cd(Ⅱ),Ni(Ⅱ),Sb(Ⅲ)和Mg(Ⅱ)...  相似文献   

3.
研究了在线氧化-流动注射-化学发光法测定痕量Cr(Ⅵ)和Cr(Ⅲ)的方法,基于槲皮素-过氧化氢-Cr(Ⅵ)-氢氧化钾化学发光直接测定Cr(Ⅵ),Cr(Ⅲ)经二氧化铅柱在线氧化后测定。方法简单、快速,Ct(Ⅵ)检出限为1.0×10~(-9)g·ml~(-1),Cr(Ⅵ)线性范围为1.0×10~(-8)~1.0×10~(-6)g·ml~(-1),用于环境水样分析,结果满意。  相似文献   

4.
报道了反相离子对液相色谱-柱后衍生化学发光检测方法分离测定痕量的钴(Ⅱ)、铁(Ⅱ)、铜(Ⅱ)、铁(Ⅲ)及铬(Ⅲ).利用弱络合性的乳酸作为淋洗剂,加入适量的十二烷基磷酸钠作对离子试剂,研究了分离条件、发光条件及二者的匹配方式等因素对分离检测的影响.测定线性范围分别为(g/mL):Cr(Ⅲ)5.0×10-9~1.0×10-5;Fe(Ⅱ)2.0×10-9~1.0×10-5;Fe(Ⅲ〕8.0×10-9~1.0×10-5;Cu(Ⅱ)8.0×10-11~1.0×10-5及Co(Ⅲ)1.0×10-11~1.0×10-5.检出限分别为:10pgCr(Ⅲ),0.4pgFe(Ⅱ),20pgFe(Ⅲ),1.0pgCu(Ⅱ)及0.01pgCo(Ⅱ).  相似文献   

5.
研究了合成的2-[(3.5-二氯-2-吡啶)偶氮]-5-氨基酚与钴(Ⅱ)的显色反应。试验结果表明,Co(Ⅱ)与该试剂在pH3.8—5.5形成紫红色络合物,最大吸收波长为546nm,ε=5.42×10~4。组成比为Co(Ⅱ):R=1:2。在25mL体积中,钴量在10—24μg范围内符合比尔定律。对8μgCo(Ⅱ),除Ni(Ⅱ)、Cu(Ⅱ)、Fe(Ⅲ)离子严重干扰外,绝大部分其它离子对测定无影响;用强碱性阴离子树脂交换可分离除去Ni(Ⅱ)。所拟定的分析方法经用于铜精矿等试样中微量钴的测定,获得满意结果。  相似文献   

6.
Fe(Ⅱ)和Ti(Ⅲ)与鲁米诺的化学发光反应已有报道,我们发现,Cr(Ⅱ)、Mo(Ⅲ)、W(Ⅲ)、U(Ⅲ)、CN-、SO32-、抗坏血酸等一大类还原剂均可与鲁米诺溶液作用产生化学发光,本文利用Jones还原柱产生V(Ⅱ),首次研究了V(Ⅱ)与鲁米诺的化学发光反应,在此基础上建立了钒的流动注射化学发光分析法,方法的检出限是8×10-11g/mL钒,线性范围是4×10-10~1×10-5g/mL钒。测定的相对标准偏差小于2%,考察了20余种常见离子对测定的干扰情况,方法已用于水样中痕量钒的测定,初步探讨了发光反应的机理。  相似文献   

7.
研究了四丁基溴化铵-KI体系分离钯的行为及与其他金属离子分离的条件。实验结果表明,在水溶液中,Pd(Ⅱ)与四丁基溴化铵和KI形成不溶于水的三元缔合物[PdI4][TBAB]2,此三元缔合物沉淀浮于盐水相上层形成界面清晰的液-固两相。当四丁基溴化铵和KI的浓度分别为7.0×10-4mol/L和2.0×10-3mol/L时,Pd(Ⅱ)的浮选率达到99.5%以上。而Ce(Ⅲ),Fe(Ⅱ),Sn(Ⅳ),Co(Ⅱ),Mn(Ⅱ),Rh(Ⅲ),Zn(Ⅱ),Ga(Ⅲ),Cr(Ⅲ),Mo(Ⅵ),W(Ⅵ),Ni(Ⅱ),Al(Ⅲ)和V(Ⅴ)离子在该体系中不被浮选,实现了Pd(Ⅱ)与这些金属离子的定量分离。对合成水样中Pd(Ⅱ)的分离和测定,结果满意。该方法在微量钯的分离和富集分析中有一定的实用价值。  相似文献   

8.
马会民  黄月仙  梁树权 《化学学报》1994,52(12):1199-1202
本文新试剂5-(2'-氨基-4'-羟基苯偶氮)邻苯二甲酰肼的合成,并研究了该试剂用于光度法测定钴的反应条件,钴与试剂在pH7.7-9.0(0.06mol.L~-1Na~2B~ 4O~ 7-HCI缓冲介质)时形成稳定配合物,最大吸收位于542nm处,摩尔吸光率为5.7×10~L.mol~-~1.cm~-~1,配合物的组成为1:2的Co:AHPP,钴浓度在0-1.02×10~-~4mol.L~-~1范围内符合Beer'slaw.试验了共存离子的影响,发现除Cu(Ⅱ),Ni(Ⅱ)略有干扰(可掩敝)外,其它常见离子均允许大量存在,该法直接用于不锈钢和维生素B~1~2 中钴的测定.  相似文献   

9.
在硫酸介质中用电生Fe(Ⅱ)作库仑滴定剂,电位法检测终点,对Cr_2O_7~(2-)、MnO_4~-离子及其混合物进行了滴定研究。试验表明,以(NH_4)_2S_2O_8溶液氧化Cr(Ⅲ)、Mn(Ⅱ)为Cr(Ⅵ)、Mn(Ⅶ)后可滴定两元素;若用稀盐酸还原Mn(Ⅶ),可滴定混合物中的Cr(Ⅵ)。当铬和锰之比从40:1到1:10变化时,混合物中两元素能依次测定。方法用于不同试样中铬和锰的分析,精度高,简便快速。  相似文献   

10.
采用微波等离子体原子发射光谱仪(MP-AES)研究了活性炭对水中微量重金属的富集性能,实现了一种简单有效,能够同时富集痕量Zn(Ⅱ),Cd(Ⅱ),V(Ⅲ),Co(Ⅱ),Ni(Ⅱ),Pb(Ⅱ),Mn(Ⅱ)和Cr(Ⅲ)8种重金属的方法。实验优化了预富集条件,包括p H值、填料量、样品速率、样品体积和洗脱条件,同时考察了常见干扰离子的影响,结果显示常见干扰离子对分析物的回收率无影响。在最优条件下,该方法对Zn(Ⅱ),Cd(Ⅱ),V(Ⅲ),Co(Ⅱ),Ni(Ⅱ),Pb(Ⅱ),Mn(Ⅱ)和Cr(Ⅲ)的检出限分别为0.45,0.35,0.25,0.06,0.40,0.25,0.20,0.20μg·L-1。该方法对10μg·L-1分析物测定的相对标准偏差(RSD,n=8)均小于5.0%。V(Ⅲ),Pb(Ⅱ)和Cr(Ⅲ)的最大富集因子为50;其他5种金属离子的最大富集因子不小于300。利用标准物质对该方法进行验证,并对实际环境水样进行测定,结果令人满意。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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