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1.
熊国华  刘虹 《分析化学》1994,22(11):1141-1144
本研究了Mn^2+和Co^2+对7-(8-羟基-3,6-二磺基萘偶氮)-8-羟基喹啉-5-磺酸-硼砂反应体系的混合荧光增敏作用。实验条件下,荧光增敏强度满足线性加和关系的范围是:Mn^2+浓度0 ̄2.9×10^-7mol/L;Co^2+浓度0 ̄8.8~10^-7mol/L;总浓度不超过1.0×10^-6mol/L。检出限量为Mn^2+4.5×10^-9mol/L和Co^2+1.4×10^-8mo  相似文献   

2.
硫羟乳酸作为络合滴定掩蔽剂的研究   总被引:2,自引:1,他引:2  
本文系统地研究了硫羟乳酸在络合滴定中的掩蔽性能。发现在pH3.0用EDTA滴定了Th^4+时,可用它掩蔽Sn^4+,Tl^3+,Sb^3+,Bi^3+,Bh^2+和Cu^2+。在pH5.5滴定Yb^3+,La^3+或Ce^3+时,可用它掩蔽Sn^4+,Tl^3+,Sb^3+,Bi^3+,Hg^2+,Cu^2+和Cr^3+,在pH10.0滴定Mg^2+时,可用它掩蔽Sn^4+,Tl^3+,Sb^3+  相似文献   

3.
本系统地研究了硫代苹果在络合滴定中的掩蔽性能,发现它在pH1.5~10可作为Sn^4+、Sb^3+、Tb^3+、Bi^3+、Cu^2+、Hg^2+和Ag^+等的掩蔽剂(在pH2~3.5还可掩蔽Fe^3+)。掩蔽上述离子后,可在pH2.5~3用Th^4+回滴EDTA,在pH5~6用EDTA滴定Zn^2+或Yb^3+等,或在pH10用EDTA滴定Mg^2+、Ca^2+、Mg^2++Ca^2+和Mn^  相似文献   

4.
庄惠生  王琼娥 《分析化学》1998,26(11):1324-1326
研究了新吖啶衍生物9,10-二甲基吖啶氟磺酸盐的化学发光特性。建立了测定Co62+的化学发光新体系。方法线性范围为1.0×10^-10-1.0×10^-7g/mL;检测限为5.0×10^-11g/mLCo^2+。测定5.0×10^-9g/mLCo62+的相对标准偏差为6.0%。方法选择性好,用于自来水,江水,池塘水中痕量钴的测定,结果令人满意。  相似文献   

5.
高锰酸钾—抗坏血酸化学发光体系测定抗坏血酸   总被引:6,自引:0,他引:6  
本文研究了高锰酸钾-抗坏血酸化学发光体系,建立了测定抗坏血酸的化学发光分析新方法,线性响应的浓度范围为5.0×10^-7mol/L~4.0×10^-5mol/L,检出限为3.0×10^-7mol/L,对2.5×10^-6mol/L抗坏血酸进行10次平行测定,相对标准偏差为1.6%,考察了22种物质的干扰情况。用于维生素C片剂及注射液中抗坏血酸含量测定,结果令人满意。  相似文献   

6.
郑建斌  刘鹏 《分析化学》1998,26(8):1014-1017
将卷积技术应用于循环示波计时电位信号的处理,提出了2.5次微分循环示波计时电位法并将其用于对铑在HCl-KBr底液中的示波性质的研究。实验结果表明:在HCl+KBr体系的示波图上,Rh^3+的特殊峰是由于铑 对氢的催化作用而产生的;在Y^2.5-E曲线上峰高与Rh^3+浓度在4×10^-7-7×10^-5mol/L范围内呈线性关系,检测下限为8×10^-5mol/L。  相似文献   

7.
在0.01mol/LNH.H2O-NH4Cl和3.0×10^-5mol/L安息香缩氨基硫脲体系中,钴产生一灵敏的还原波,其峰电位是-0.94V(vs.SCE),峰电流与钴的浓度在2.0×10-8-1.0×10^-6mol/L范围内成直线关系,检测限为5.0×10^-9mol/L,该法测定水中痕量钴结果令人满意。  相似文献   

8.
乳酸环丙沙星单扫描示波极谱法研究   总被引:3,自引:0,他引:3  
研究了乳酸环丙沙星的极谱伏安行为,在pH=8.3的0.02mol/L,NH4Cl-NH3.H2O底液中,乳酸环丙沙星能产生1个灵敏的还原峰,峰电位为-1.61V,其导数峰高与浓度在3.9×10^-8~1.8×10^-6mol/L和1.8×10^6~1.1×10^-5mol/L范围内呈现良好的线性关系,相关系数r=0.9997,检测下限为2.5×10^-8mol/L,用于乳酸环丙沙星注射液的测定,相  相似文献   

9.
宋俊峰  高雅芳 《分析化学》1995,23(4):438-441
本报道一种测定哌仑西平的单扫描示波极谱法,在0.1mol/LNH4Cl-NH3.H2O(pH8.0±0.1)缓冲液中,哌仑西平有一极谱还原波,其峰电位为-1.51V(vs.SCE),其一阶导数峰高与哌仑西闰浓度在6.6×10^-7-4.6×10^-6mol/L(r=0.9981)和6.6×10^-6-1.6×10^-5mol/L(r=0.9991)范围内有线性关系,检测限为3.4×10-7mol  相似文献   

10.
全固定化试剂流动注射化学发光测定铜   总被引:5,自引:3,他引:5  
采用离子交换固定法把Luminol(Lu),CN^-固定在阴离子交换树脂上,串入流动注射系统中,当一定量洗脱剂被注入阴离子交换柱时,洗脱下来的Lu和CN^-与分析物Cu^2+发生化学反应,产生化学发光,实现对Cu^2+的在线检测。本法检出限为1.3×10^-9g/mL,线性范围为4.0×10^-9-6.0×10^-6g/mL,RSD为3.4%,单次测定在1min内能完成。已用于井水中铜的测定,结果  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.
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   

16.
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   

17.
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   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

19.
20.
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   

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