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1.
碘的凝胶色谱测定方法   总被引:6,自引:1,他引:6  
丁朝武  李华斌 《分析化学》1997,25(5):586-589
建立了碘折凝胶色谱测定方法。色谱条件为:Shim-pack DIOL-150柱;流动相甲醇0.01mol/L H3PO4(10:90)流速为1.2mL/min;柱温为35℃,检测波长为224nm;线性范围是0.010-1.0mg/L,相关系数为0.9993,检测限为0.001mg/L,相对标准偏差为1.2%-4.6%;回收率为91%-98%。所建立的方法已用于食盐,尿,系带等样品的测试,均取得较好  相似文献   

2.
用凝胶渗透色谱法在三种不同孔径大孔硅质二醇固定相上,快速定量测定了化学驱油体系中部分水解的聚丙烯酰胺,该方法以大二醇硅质SI-500,SI-1000,SI-3000(孔径分别为50nm,100nm和300nm)为固定相,以0.2mol/L及0.5mol/L,NaH2PO4为流动相,在210nm处检测,表面活性剂及聚合物驱油液中所有组分对聚丙烯酰的测定均无干扰,最低检测限为2mg/L~4mg/L,回  相似文献   

3.
中性红褪色光度法测定水中二氧化氯   总被引:1,自引:0,他引:1  
1引言二氧化氯(ClO2)是广谱杀菌消毒剂,空气或水中百万分之几的CO2,即可发挥作用.在多种测定方法中褪色光度法较简便易行,国外报道该类方法检测下最低达0.01mg/L,最宽线性范围为0~2mg/L.本文研究了中性红的褪色反应,所建立的光度法其检测下限达0.01mg/L,线性范围0~3.mg/L,可用于水中ClO2测定.2实验部分2.1仪器及试剂岛津UV-240分光光度计.中性红(指示剂级)、蒸馏水.其它试剂皆为分析纯.中性红溶液:准确称取中性红mol/L硫酸溶解配成1.0×10-3mol/L…  相似文献   

4.
司炜  张金锐 《分析化学》1997,25(1):115-118
开发了一种新的0.1-1.0mg/L痕量硫的分析系统及方法,方法以Antek7000氧化裂解-紫外荧光定硫仪为基础,通过对进样系统、裂解管、及检测限等方面的改进、使单次分析样品最大进样量增加到50μL。方法的检测限达到0.1mg/L,满足了科研及生产工艺的需要。  相似文献   

5.
基于固定化酶的流动荧光法测定血清中的葡萄糖   总被引:5,自引:0,他引:5  
宫志龙  章竹君 《分析化学》1996,24(9):998-1001
本文将固定化酶柱,光纤以及停流技术结合起来,研究了以廉价而易得的硫胺素为荧光底物的葡萄糖的荧光分析,提出了一种快速、简便、精确地测定葡萄糖的新方法。其线性范围为1.0 ̄60.0mg/L,线性相关系数为0.999,检测限为0.15mg/L。以5.0mg/L的葡萄糖作精度试验,RSD%=2.1%(n=11)。该方法已成功地用于血清中葡萄糖的测定,结果与光度法相符。  相似文献   

6.
研究了肼对中性红与亚硝酸根之间反应的抑制作用,建立了动力学光度法测定肼的新方法,方法的线性范围为0.15-1.0mg/L,检出限为0.10mg/L。应用于水样中肼的测定,结果满意。  相似文献   

7.
不完全抑制电导检测离子色谱法测定饮料中的苹果酸   总被引:2,自引:0,他引:2  
朱岩  徐素君  王素芬 《分析化学》1999,27(9):1050-1053
采用一种抑制型离子色谱检测技术--不完全抑制电导检测,以0.75mmol/LNa2SO4+NaOH(pH=11.5)为淋洗液对弱酸根离子如苹果酸、酒石酸等进行了测定,得到苹果酸、酒石酸的检测限分别为1.31mg/L、3.04mg/L;在200mg/L以下相关系数分别为0.9998、0.9999;;各离子峰高的相对标准偏差(RSD)分别为0.57%、1.60%。上率为97.7 ̄104%。常见的强酸离  相似文献   

8.
应用水解还原铁(Ⅲ)—邻二氮菲光度法测定丙酮肟   总被引:1,自引:0,他引:1  
成凤桂  雷海 《分析化学》1999,27(5):551-554
丙酮肟在酸性条件下经加热水解生成个有还原性的羟胺,并将Fe(Ⅲ)定量还原为Fe(Ⅱ),应用Fe(Ⅱ)-邻二氮菲光度法简接测定丙酮肟。选择了水解最佳条件(加热温度、时间、介质酸度、显以剂的加入顺序等)。结果表明,测定线性范围为0 ̄1.2mg/L。相关系数r=0.9998,最低检测浓度为0.046mg/L,RSD〈3.3%(n=5)。应用该法测定火力发电厂锅炉运行水中丙酮肟的含量,方法简便,灵敏度高。  相似文献   

9.
居室空气中甲醛的气相色谱法分析   总被引:27,自引:0,他引:27  
张存玲  于剑  翟敏德 《色谱》1998,16(4):363-364
建立了测定居室空气中甲醛的衍生气相色谱法。方法的检测限为0.02mg/L(水溶液),当采气量为10L时,最低检出浓度为0.01mg/m3(居室空气),变异系数为4.1%~6.5%,回收率为71.0%~90.4%。  相似文献   

10.
粘度法研究胶态分散凝胶交联过程   总被引:27,自引:0,他引:27  
通过粘度测定方法,研究了部分水解聚丙烯酰胺(HPAM)/ 柠檬酸铝(AlCit) 交联过程中粘度变化的特性.聚合物浓度高的HPAM/AlCit 体系粘度随反应时间的延长而上升,其体系粘度最终高于相同聚合物浓度的HPAM 溶液粘度.聚合物浓度低的HPAM/AlCit 体系粘度随反应时间的延长而下降,其体系粘度低于相同聚合物浓度的HPAM 溶液粘度.HPAM/AlCit 交联体系的聚合物浓度低于临界浓度时,交联反应后形成稀胶态分散凝胶(TCDG) .在实验条件下,临界浓度在150 ~300mg/L 之间.当聚合物浓度于临界浓度和700mg/L之间时,形成浓胶态分散凝胶(CCDG) ;当聚合物浓度高于700mg/L 时,HPAM/AlCit 交联体系形成整体凝胶.  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.
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.
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   

17.
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   

18.
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   

19.
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   

20.
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