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31.
本文简述了红外热成像技术用于厚膜混合集成电路热设计中的理论与实验方法,并讨论了结果。  相似文献   
32.
High-performance liquid chromatography (HPLC) enantioseparation of terazosin (TER) was accomplished on the immobilised-type Chiralpak IC chiral stationary phase (CSP) under both polar organic and reversed-phase modes. A simple analytical method was validated using a mixture of methanol–water–DEA 95:5:0.1 (v/v/v) as a mobile phase. Under reversed-phase conditions good linearities were obtained over the concentration range 8.76–26.28 μg mL−1 for both enantiomers. The limits of detection and quantification were 10 and 30 ng mL−1, respectively. The intra- and inter-day assay precision was less than 1.66% (RSD%). The optimised conditions also allowed to resolve chiral and achiral impurities from the enantiomers of TER. The proposed HPLC method supports pharmacological studies on the biological effects of the both forms of TER and analytical investigations of potential drug formulations based on a single enantiomer. At the semipreparative scale, 5.3 mg of racemic sample were resolved with elution times less than 12 min using a mobile phase consisting of methanol–DEA 100:0.1 (v/v) and both enantiomers were isolated with a purity of ≥99% enantiomeric excess (ee). The absolute configuration of TER enantiomers was assigned by comparison of the measured specific rotations with those reported in the literature.  相似文献   
33.
牛立元  沈振国 《色谱》2009,27(6):829-834
利用阴离子交换色谱柱及紫外-可见光检测器建立的离子色谱分析方法对植物及土壤中乙二胺二琥珀酸([S,S′]-ethylenediaminedisuccinic acid,EDDS)金属(Fe(III)、Pb、Cu、Zn和Mn)复合物进行了分析,并用电喷雾质谱对其进行了确认。实验选用戴安IonPac AS11-HC阴离子交换色谱柱(250 mm×4.2 mm,5 μm)及保护柱,以60 mmol/L硝酸铵溶液(pH 6.5)为洗脱液,在1.0 mL/min流速下进行等度洗脱,检测波长为260 nm。金属-EDDS复合物的质谱鉴定采用选择离子扫描模式。结果表明,该方法可以用于Fe(III)-、Pb-、Cu-EDDS复合物的分离测定,三者的检出限分别是0.38,0.54和0.18 μmol/L,回收率分别是99.6%,100.6%和97.5%。该方法操作简单、灵敏,适合于植物样品及土壤样品中含有的Fe(III)-、Cu-和Pb-EDDS复合物的单独或同时分析鉴定。  相似文献   
34.
钟志雄  李攻科 《色谱》2009,27(4):499-504
建立了离子色谱法测定海产品中磷酸盐、焦磷酸盐、偏磷酸盐和总磷的分析方法。样品经100 mmol/L NaOH溶液浸提,固相萃取柱去除有机物、阳离子、中和OH~后用于海产品中磷酸盐、焦磷酸盐和偏磷酸盐的测定;样品经干灰化法消化,固相萃取柱净化后用于总磷测定。考察了提取溶液的pH、有机物和共存离子对测定结果的影响。该方法的线性范围为0.3~60 mg/L,检出限为2.1~2.3 mg/kg,相对标准偏差为1.6%~2.6%。海鱼和虾仁样品中目标物的加标回收率为81.8%~100.0%。该方法选择性好,灵敏度高,用于实际样品测定结果令人满意。  相似文献   
35.
Antimony is a toxic metalloid and is often present in inorganic forms such as more toxic Sb(III) and less toxic Sb(V). Auto brake linings are major contributors to antimony emissions along heavily traveled highways. In this study the distribution of water extractable Sb(III) and Sb(V) species along a Massachusetts highway was investigated. Antimony complexed to roadside soil-derived humic acids was studied by ion chromatography (IC) and size exclusion chromatography (SEC) coupled to inductively coupled plasma-mass spectrometry (ICP-MS). Thirty surface soil and soil core samples along route 116 in western Massachusetts were collected. Two soil-derived humic acids were extracted from the roadside soils. Elevated levels of nitric acid-extractable Sb (range: 2.9-24.9 µg/kg) and Pb (range: 10.4-2420 mg/kg) were found in the soil along the road and correlated well with highway traffic patterns. Sb(V) was the dominant species present in both surface and soil core samples, and is mostly confined to the top 20-cm layer of soil. HA mediated Sb(III) to Sb(V) oxidation was relatively fast and demonstrated pseudo-first order kinetics, where pseudo rate constant k is 3.033 h-1. Antimony bound to soil-derived humic acid molar mass fractions was identified.  相似文献   
36.
Copper(II) complexes of the type [Cu(SPF)(Ln)Cl] (where SPF is sparfloxacin and Ln = substituted terpyridines) were synthesized and found to have a distorted octahedral geometry. Superoxide dismutase‐like activity of the complexes was measured using a nitroblue tetrazolium/reduced nicotinamide adenine dinucleotide/phenazine methosulfate system and expressed in terms of the concentration of complex which terminates the formation of formazan by 50% (IC50 value), which was found to range from 0.572 to 1.522 µm . Interactions of the complexes with herring sperm DNA were studied by absorption titration, viscosity measurement and gel electrophoresis under physiological conditions. The antimicrobial efficiency of the complexes was tested against five different microorganisms and showed good biological activity. All the complexes showed good cytotoxic activity, with LC50 values ranging from 4.01 to 9.64 µg ml?1. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
37.
This paper reports the results on a study of ion chromatography (IC) behaviour on strong cationic exchange column of CH3-(CH2)n−1-NH2 (n=1-6) type linear monoamines. The eluents were mixtures of HCl-NaCl, HNO3-NaNO3, HClO4-NaClO4, H2SO4-Na2SO4, HClO4-NaClO4-CH3CN. Amines were revealed with an amperometric detector. The influence of different counter-ions on retention factors, k′, is discussed. Relationships between k′ and pE (E=sum of Na+ and H+ concentrations), and length of alkylic chain, and sensitivity coefficient S, are reported and discussed. The addition of acetonitrile (ACN) in the eluent was also taken into account. Suitable considerations are derived from these data. An example of monoamines separation is given.  相似文献   
38.
应用离子色谱法同时测定不同时段酸雨中17种离子的含量。样品经离心沉淀后,经0.45μm滤膜过滤,滤液供离子色谱分析。阴离子分离时用Shodex SI-52 4E阴离子色谱柱,并用3.6mmol·L-1碳酸钠-0.6 mmol·L-1碳酸氢钠缓冲溶液作为淋洗液;阳离子分离时用TSKGEL阳离子色谱柱,并用2mmol·L-1硝酸溶液作为淋洗液,采用电导检测器进行检测。17种离子均在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在1.4~18.7μg·L-1之间。回收率在95.0%~105%之间,测定值的相对标准偏差(n=6)在1.7%~7.2%之间。  相似文献   
39.
建立了测定电子烟烟液中的氨含量离子色谱法。样品经10 mol·L-1盐酸溶液萃取10 min后,采用Dionex Ion Pac CS16A阳离子交换柱分离,以MSA为淋洗液进梯度洗脱,用电化学检测器检测。氨的质量浓度在0.05~1.0 mg·L-1范围内与峰面积呈线性关系,检出限(3S/N)为0.035μg·g-1,测定下限(10S/N)为0.12μg·g-1。方法用于12种市售品牌电子烟烟液中氨的测定,加标回收率在93.2%~106%之间,测定值的相对标准偏差(n=5)小于4%。  相似文献   
40.
采用离子色谱法同时测定沙棘果粉中7种有机酸含量。样品与氢氧化钾溶液经振荡反应后过0.22μm离子滤膜,采用IonPac AG19阴离子保护柱和IonPac AS19阴离子分析柱分离,以氢氧化钾溶液进行梯度淋洗,电导检测器检测。7种有机酸的质量浓度在一定范围内与其峰面积呈线性关系。对沙棘果粉样品进行加标回收试验,7种有机酸的回收率在94.0%~109%之间,测定值的相对标准偏差(n=11)在0.20%~3.1%之间。  相似文献   
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