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1.
应用火焰原子吸收光谱法测定了6种温里类中草药(即香附子、干姜、肉桂、细辛、高良姜及小茴香)中4种痕量元素铜、铁、锌及锰的含量。样品用硝酸-高氯酸(4+1)混合酸消解后加入过氧化氢,并蒸发至近干,残渣溶于硝酸(1+99)溶液中后用于火焰原子吸收光谱法分析,标准曲线分别用上述4种元素的标准溶液制作。按此方法分析了上述6种中草药中铜、铁、锌及锰4种痕量元素,并在此基础上用标准加入法作了回收试验,测得4种痕量元素的回收率在93.5%~109.0%之间。  相似文献   

2.
目的使用微波消解和热酸溶液直接溶解板蓝根颗粒,运用火焰原子吸收光谱法测定这两种溶液中Fe、Zn、Cu、Mg、Ca和Mn 6种金属元素的含量。方法分别采用浓HNO3湿法微波消解和直接溶解板蓝根颗粒样品,用原子吸收分光光度计测定上述样品中6种金属元素含量。结果所测定的板蓝根颗粒中含有丰富的金属元素,两种前处理方法测定的结果相差很小。采用此法回收率在92.0%~110.0%之间,样品相对偏差小于3%。结论板蓝根颗粒中金属元素可作为人体元素的重要补充。  相似文献   

3.
生姜、大蒜和辣椒中六种微量元素的测定   总被引:1,自引:0,他引:1  
用浓硝酸和双氧水微波消解处理样品,采用火焰原子吸收光谱法测定了生姜、大蒜和辣椒中Fe、Cu、Mg、Ca、Mn、Zn6种元素的含量。结果表明,这3种植物中含有丰富的人体必需微量元素,样品回收率在94.O%~101.8%之间。该法操作简单,结果准确。  相似文献   

4.
用3种不同的样品前处理方法,即①常规湿法酸消解法、②微波加热酸消解法及③干灰化法分别对川芎样作前处理溶解,用石墨炉原子吸收光谱法(GF-AAS)测定试液中铅、铜和镉的含量,用氢化物发生-原子荧光光谱法(HG-AFS)测定试液中砷和汞的含量。结果表明:用方法①及方法③处理样品所得溶液中,铅、铜和镉的回收率在83.0%~121.0%之间,而汞和砷的回收率很低。在方法②处理样品所得溶液中,测得砷、铜、镉及汞的回收率达97.0%~127.0%之间,而铅的回收率较低,仅为51.8%。总之,方法①适合用于GF-AAS测定铅时的样品前处理,方法②宜用于HG-AFS测定汞和砷时的样品前处理,而方法③宜应用于GF-AAS测定铜及镉时的样品前处理。  相似文献   

5.
微波消解样品-火焰原子吸收光谱法测定重晶石中铅   总被引:2,自引:0,他引:2  
研究了火焰原子吸收光谱法测定重晶石中铅的方法.重晶石样品用王水3 mL于消解罐中,于微波消解仪中消解8 min,比常压和增压两种酸浸提法节省3 h.浸出率和分析精密度均优于常压酸浸提法,对重晶石样品中铅测定值的相对标准偏差为1.8%~5.7%,回收率为95%~103%.  相似文献   

6.
用浓硝酸微波消解的方法处理样品,采用火焰原子吸收光谱法测定了中药山绿茶中Fe、Cu、Mg、Ca、Mn、Zn6种微量元素的含量。结果表明,山绿茶含有丰富的人体必需微量元素,各元素的回收率在98.00%~101.10%之间。该方法操作简单,结果准确,是山绿茶中微量元素测定的理想方法。  相似文献   

7.
探索并建立微波消解-火焰原子吸收光谱法测定真菌菌丝Cd含量的方法。采用家用微波炉配合微波消解罐,组成经济实用的微波消解系统,对富含Cd的深色有隔内生真菌(DSE)菌丝进行微波消解,火焰原子吸收光谱法测定Cd浓度。结果表明:采用5 mL浓HNO3为消解剂,先中火(528 W)微波加热5min,然后高火(800 W)微波加热8 min的微波消解程序,能够完全消解0.050 g的粉状DSE干菌丝,该微波消解法对Cd2+标准物的回收率为94.09%~102.22%,精密度优于常规湿法消解。  相似文献   

8.
火焰原子吸收光谱法测定三种产地黑米中微量元素含量   总被引:1,自引:0,他引:1  
用微波消解黑米样品,火焰原子吸收光谱法测定了3个不同产地黑米中Fe、Cu、K、Mn、Mg、Zn 6种微量元素含量。结果表明,微波消解时间短,操作简单,节省试剂,环境污染少,各元素回收率在95.2%~103.5%之间,相对标准偏差(RSD)均〈5%。  相似文献   

9.
采用微波法消解样品,用火焰原子吸收光谱法分别测定了小叶黄杨木不同部位的钙、镁、铁、铜、锌、锰和钴含量,以及该植物对不同金属元素吸收情况.7种金属元素的线性回归方程的相关系数在0.996~0.999之间,各元素平均加标回收率在94.0%~109.5%范围,相对标准偏差(n=5)为2.1%~6.6%.  相似文献   

10.
微波消解-火焰原子吸收法测定土壤中的钴   总被引:1,自引:0,他引:1  
建立了微波消解一火焰原子吸收法测定土壤中钴的方法:用微波消解土壤、电热板加热驱酸的方法对土壤样品进行前处理,优化了微波消解条件。方法的加标回收率为93.0%~106.0%,检出限为3.0μg/g,测定结果的相对标准偏差为2.1%~4.9%(n=6)。  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.

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   

13.
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   

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.
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   

17.
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   

18.
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   

19.
20.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

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