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1.
用空气-C2H2火焰原子吸收光谱法测定了中草药中的Fe、Mg含量,讨论了测定条件,结果令人满意,方法的回收率:Fe98.20%-104.9%,CV1.06%-1.07%,Mn99.4%-101%,CV=0.52%-1.94%。  相似文献   

2.
用空气-C2H2火焰原子吸收光谱法测定了中草药(鸦胆子、补骨脂)中的Fe、Mg含量,讨论了测定条件,结果令人满意,方法的回收率:Fe98.20%~104.9%,CV=1.06%~1.07%,Mn99.4%~101%,CV=0.52%~1.94%。  相似文献   

3.
本文用双波长吸光度比值K系数法同时测定撒痛风注射液中水杨酸钠,咖啡因和安替比林三组分的含量,其平均回收率及变异系数分别为101.5%,0.40%;99.99%,0.37%;100.0%,0.30%。既改善了选择性,又提高了灵敏度,弥补了常规K系数法的不足。  相似文献   

4.
依据系统工程理论的原理和方法,研究了Sr、B、Zn、Mo、Cu五种微显元素对中甘11号结球甘蓝产量、品质的影响及各因子间的复合效应。试验结果表明,各因子对中甘11号产量的作用是:Sr>B>Zn>Cu>Mo。获得了中甘11号亩产在6000kg以上的优化组合方案是:Sr0.054%~0.061%,B0.035%~0.042%,Zn0.047%~0.057%,Mo0.032%~0.038%,Cu0.050%~0.056%,为微量元素在蔬菜上的应用提供了科学依据.  相似文献   

5.
采用火焰原子吸收光谱法测定了鸦胆子,补骨脂中Ca,Mg含量,建立了样品消化方法及抑制介质基体对测定影响的措施,确立了方法的可行性。方法的回收率:Mg98.80%-102.8%,Ca96.20%-104.4%;相对标准偏差小于1.04%。  相似文献   

6.
调查了234例0-6岁儿童头发锌,铁,钙及铅含量。结果显示,存在食欲不振者90.59%,反复发生呼吸道感染及肠道感染者占55.98%,严重生长迟缓者占7.89%;缺锌儿童占调查总数的40.59%,缺铁者占34.62%,缺铁者占27.77%。  相似文献   

7.
ICPMS测定高纯氧化钇中痕量稀土杂质的研究   总被引:14,自引:0,他引:14  
研究了直接电感耦合等离子质谱(ICPMS)测定99.999%纯度氧化钇中稀土杂质的方法,详细探讨了仪器工作参数对稀土元素的测定的影响,对各种干扰现象进行了研究,并提出定量校正方法,实验表明,加入内标元素可有效地克服基体效应、接口效应和仪器工作参数漂移的影响。方法的检出限为0.003~0.02ng/ml,变异系数(CV%)为0.2%~5.4%,回收率为90%~115%。适合99.0%~99.999%  相似文献   

8.
石墨炉原子吸收光谱法测定蘑菇中的镉、铅   总被引:11,自引:0,他引:11  
马戈  谢文兵  于桂红  朱秀梅 《分析化学》2003,31(9):1109-1111
采用石墨炉原子吸收光谱法测定蘑菇中的镉、铅,以磷酸二氢铵和硝酸镁作混合基体改进剂,提高了测定的灰化温度,消除了基体干扰。方法简便,快速,准确度高。镉和铅的相对标准偏差为3.7%-6.0%和7.3%-7.9%;回收率为98%-106%和98%-104%;检出限为0.009μg/g和0.032μg/g。  相似文献   

9.
使用微波增压溶样法,将样品用HNO3—HClO4溶解后,用石墨炉原子吸收光谱法同时测定植物性样品中铅和镉。以磷酸二氢铵—硝酸镁作为基体改进剂,可使灰化温度大大提高,克服了基体的干扰。铅和镉的回收率分别为95.3%—104.8%和96.2%—105.5%,RSD分别为4.8%-7.2%和4.3%-7.6%。  相似文献   

10.
建立了反相离子对色谱用于测定制剂中舒必利的含量。采用C8柱,流动相为35%甲醇-65%的0.1mol/L甲酸铵缓冲液(含已烷磺酸钠,pH=3.5),检测器UV290nm,片剂中舒必利平均回收率为98.88% ̄100.92%,样品测试日内及日间RSD分别为1.04% ̄2.29%及1.85% ̄3.02%。  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.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

14.
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   

15.

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   

16.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.  相似文献   

18.
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   

19.
潘素娟  全灿  周俊波 《化学通报》2014,77(12):1165-1170
测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。  相似文献   

20.
微量钙的测定方法研究进展   总被引:5,自引:0,他引:5  
介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。  相似文献   

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