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1.
甲壳素色谱柱富集—柱前显色分光光度法快速测定痕量铜   总被引:1,自引:0,他引:1  
本文研究了甲壳素柱快速吸附Cu(I)-2,9-二甲基-4,7-二苯基-1,10-邻菲罗啉-十二烷基苯磺酸钠橙红色的缔合物,用乙醇-乙酸的混合液洗脱后,在分光光度计上直接测定洗脱液的吸光度,方法简便、快速,富集倍数高,可用于水样中痕量铜的测定。  相似文献   

2.
报道了一种在线柱分离ICP-MS快速测定高纯氧化铕中杂质铥的方法,采用一种新型膦酸类萃取剂,大大降低了林洗酸度,洗脱液中的Tm直接进入ICP-MS进行在线测定。整个分离测定周期为40min,方法检出限为0.12ng/mL,加示加收率为91.5%-98%,RSD为4.1%,该方法快速,简便。用于高纯氧化铕中杂质铥的测定,结果满意。  相似文献   

3.
研究了甲壳素色谱柱富集Fe(Ⅲ)-磺基水杨酸-十八烷基十甲基氨基乙酸的红紫色缔合物,用磺基水杨酸洗脱后,在分光光度计上直接测定洗脱液的吸光度,方法快速,简单、富集倍数高,用于环境水样中痕量铁的测定,结果令人满意。  相似文献   

4.
合成了全硅ZSM-5分子筛,制备了一种新型的全硅ZSM-5分子筛填充柱,成功地在室温下进行了O2,N2分离,并利用物化色谱法,准确而快速地测定了O2,N2在全硅ZSM-5分子筛填充柱上的吸附热。  相似文献   

5.
锌柱还原分光光度法测定微量砷   总被引:4,自引:0,他引:4  
俞长兴  高英立 《分析化学》1997,25(5):531-533
对锌柱还原砷及其测定进行了研究,胂化氢以Ag^+-PVA-EtOH-H2O为吸收液,在λmax400nm处进行吸光度测定,砷在0-1.8mg/L范围内与吸光度呈良好线性关系,其ε=8.7×10^4L.mol^-1.cm^-1。检出限为24μg/L。  相似文献   

6.
微型镉柱还原分光光度法测定血清中一氧化氮   总被引:3,自引:0,他引:3  
建立了微型镉柱还原法间接测定血清中一氧化氮的新方法。本方法还原硝酸根所需时间短,还原率达95%以上,用于测定混合血清中一氧化氮。检测范围为0-1000μmol/L,相对标准偏差为1.70%-2.49%,对NO^-3的回收率为95.8%-104.0%,对NO^-2的回收率为93.6%-96.8%。  相似文献   

7.
建立了氯化亚锡还原-硫氰酸铵快速光度法测定合金钢中钨的方法,方法的线性范围为2-400μg/50mL,相对标准偏差为0.24%-1.22%,方法简便,快速,测定结果准确。  相似文献   

8.
脱线柱预富集 ICP-MS法测定南极水样中的痕量元素   总被引:9,自引:0,他引:9  
采用脱螯合阳离子树脂(D401)将待分析元素预富集并与基体元素分离,采用电感耦合等离子体质谱法(ICP-MS)测定了极拉斯曼丘陵地区环境水样中的难于或不能直接检测的超痕量元素Mn,Co,Ni,Cu,Cd,Ba和Pb;建立了一种准确,简便、快速的在线加内标准方法,被分析元素的测定灵敏度均提高了30倍左右;对于100mL,水样检测限为1.425ng/L-24.84ng/L。  相似文献   

9.
一种新型水硬度测定的进样装置   总被引:1,自引:0,他引:1  
王洁清  陈文闯 《分析化学》1998,26(4):485-488
报道一种新型水硬度测定的进样装置,它是特殊的直接进样-混合-混合-排液系统,勿需预先显色,可直接进样测定。实验表明具有操作简便,快速的优点。  相似文献   

10.
侯艳文  牟世芬 《分析化学》1997,25(11):1241-1245
提出了用离子色谱柱后衍生法同时测定汞和其它金属离子的新方法。本方法中样品离子以阴离子交换分离,用2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚和非离子表面活性剂TritonX-100显色体系作柱后衍生,分光光度法测定。  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   

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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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