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1.
锰(Ⅳ)-安乃近-甲醛化学发光体系的研究   总被引:3,自引:0,他引:3  
实验发现锰(Ⅳ)氧化安乃近可以产生弱的化学发光,甲醛对这一化学发光反应有较强的增敏作用。据此建立了测定安乃近的流动注射化学发光分析法。在最优化的条件下,测定安乃近的线性范围为6 0×10-7~1 0×10-5mol/L,检出限为2×10-7mol/L安乃近。对1.0×10-6mol/L安乃近进行11次测定,相对标准偏差为3.4%。该方法已应用于针剂中安乃近的测定,其结果与药典方法测得值一致。  相似文献   

2.
以水合肼为还原剂,采用均相还原法制备还原氧化石墨烯-多壁碳纳米管复合材料(rGO-MWCNTs),通过滴涂法将其修饰到玻碳电极(GCE)表面.以此复合材料为载体,采用电化学方法制备了金纳米粒子-还原氧化石墨烯-多壁碳纳米管复合膜修饰电极(AuNPs-rGO-MWCNTs/GCE).通过扫描电镜(SEM)、EDS能谱技术和电化学方法对此电极进行了表征.研究了双酚A在修饰电极上的电化学行为.结果表明,此电极对双酚A的电极过程具有良好的电化学活性,在0.10 mol/L PBS溶液(pH 7.0)中,微分脉冲伏安法测定双酚A的线性范围为5.0 × 10-9~1.0 × 10-7 mol/L和1.0 × 10-7~2.0 × 10-5 mol/L,检出限为1.0 ×10-9 mol/L(S/N=3). 将此电极用于模拟水样和超市购物小票样品中双酚A含量的测定,加标回收率分别为97%~110%和98%~104%.  相似文献   

3.
流动注射化学发光法测定盐酸羟苄唑   总被引:1,自引:0,他引:1  
基于在碱性条件下盐酸羟苄唑能够与鲁米诺产生化学发光的现象,建立了流动注射化学发光测定盐酸羟苄唑的新方法。盐酸羟苄唑的浓度在8×10-7~1×10-4mol/L范围内与化学发光强度呈良好的线性关系,方法的(3σ)检出限为3×10-7mol/L,对1×10-5mol/L的盐酸羟苄唑连续11次测定的相对标准偏差为1.7%,回收率为96%~103%。已用于滴眼液中盐酸羟苄唑的测定。  相似文献   

4.
建立了测定塑料饮料瓶中双酚A的Brij35增敏荧光分析法.实验考察了不同介质及pH、静置时间、介质用量、金属离子等因素对双酚A(BPA)荧光强度的影响.结果表明,在所探讨的7种介质中Brij 35荧光增敏效果最好,据此建立了一种用Brij35增敏荧光光度法测定双酚A的新方法.方法线性范围为2.0×10-8~1.0×10-5 mol/L,检出限为2.5×10-8 mol/L,相对标准偏差为1.92%.该方法快速、简便、灵敏度高,对实际样品塑料饮料瓶中双酚A的检测,结果满意.  相似文献   

5.
流动注射化学发光法测定叶酸   总被引:5,自引:0,他引:5  
建立了用高锰酸钾 -硫酸 -甲醛 -叶酸化学发光体系测定叶酸的新方法。方法的检出限为 2 .4× 10 -8mol/ L,叶酸浓度在 1.0× 10 -7~ 1.0× 10 -5 mol/ L范围内与化学发光强度呈良好的线性关系。对 4.0× 10 -6 mol/ L叶酸进行 11次平行测定 ,方法的相对标准偏差为 1.7%。该法用于叶酸片剂中叶酸含量的测定 ,结果与药典标准方法测得值一致 ,回收率为 97.3%~ 10 3.8%。  相似文献   

6.
提出了Ru(bipy) 2+ 3-CO 2- 3-SO 2- 3-KClO 3体系化学发光法测定溶液中亚硫酸盐的方法.SO 2- 3浓度与化学发光强度在1.0×10-7~1.0×10-4 mol/L 范围内成正比,检出限为8.76×10-8 mol/L,对1.0×10-4 mol/L SO2-3溶液6次测定的相对标准偏差为2.9%.该法用三乙醇胺作为吸收液,成功地用于测定空气中二氧化硫的含量,结果满意.  相似文献   

7.
分子印迹-化学发光分析法测定安乃近   总被引:7,自引:0,他引:7  
以甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了安乃近分子印迹聚合物,对其性能进行了Scatchard分析;以此聚合物为分子识别物质,利用锰()-甲醛-安乃近化学发光体系,结合流动分析技术,建立了高选择性测定安乃近的分子印迹-化学发光分析方法.该方法的线性范围为1.0×10-7~1.0×10-5mol/L,检出限为4×10-8mol/L,对1.0×10-6mol/L安乃近溶液平行测定7次的相对标准偏差为2.4%.该方法已用于尿液中安乃近的直接测定.  相似文献   

8.
张四纯  李华  武亚艳 《分析化学》2001,29(2):150-153
新合成的N(2-四氢苯并噻唑)-2-羟基苯甲亚胺希夫碱与酸性高锰酸钾反应产生微弱的化学发光,甲酸的存在有显著的增敏作用。报道了其荧光光谱、化学发光光谱、紫外可见吸收光谱和化学发光动力学曲线,并建立了流动注射化学发光测定噻唑类希夫碱的方法。该法线性范围为1.0×10-7~8.0×10-5mol/L,检测限为5.0×10-8mol/L,对1.0×10-6mol/L噻唑类希夫碱11次平行测定的相对标准偏差为1.7%。  相似文献   

9.
基于新合成的噻唑类希夫碱.N-(2-四氢苯并噻唑)-2-羟基苯甲亚胺对Ce4+与SO32-反应产生的微弱化学发光的增敏作用,建立了流动注射化学发光测定噻唑类希夫碱的方法。该法线性范围为8.0×10-5~2.0×10-7mol/L;检出限为5.0×10-8mol/L;对2.0×10-7mol/L噻唑类希夫碱7次平行测定相对标准偏差为2.2%。  相似文献   

10.
流动注射化学发光法测定水样中痕量间苯二酚   总被引:3,自引:0,他引:3  
基于在甲醛存在条件下,高锰酸钾在酸性介质中氧化间苯二酚而发生化学发光反应,建立了测定痕量的间苯二酚化学发光分析法.该法测定间苯二酚的线性范围为5.0×10-9~1.0×10-4mol/L,检出限为3.0×10-9mol/L,相对标准偏差为3.5%(1.0×10-6mol/L间苯二酚,n=11).该法应用于测定水样中加入的间苯二酚,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.
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.
19.
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   

20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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