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流动注射化学发光法测定没食子酸 总被引:4,自引:0,他引:4
基于在碱性介质中,没食子酸(Gallicacid)被过氧化氢氧化能产生化学发光,而甲醛对该体系的化学发光有较强增敏作用,据此建立了流动注射化学发光法测定没食子酸的新方法。该法简单、快速、线性范围较宽。本法测定没食子酸的线性范围为2.0×10-6~2.0×10-4g/mL,检出限达5.8×10-7g/mL,采样频率为120个/小时。对4.0×10-5g/mL没食子酸溶液连续11次测定的相对标准偏差为2.52%。该方法已成功地用于橄榄中没食子酸含量的测定。 相似文献
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本文发现了异烟肼在铁氰化钾-钙黄绿素化学发光反应体系中的后化学发光反应。优化了反应条件,建立了一种利用后化学发光反应测定异烟肼的流动注射化学发光分析法。方法的检出限为6×10-8g/mL, 相对标准偏差为1.8% (2.0×10-6 g/mL 异烟肼,n=11),线性范围为2.0×10-7~1.0×10-5 g/mL。此法已用于异烟肼片剂中异烟肼含量的测定,结果与药典方法测定值一致。 相似文献
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反向流动注射化学发光法测定五氟利多 总被引:4,自引:2,他引:4
基于五氟利多对 KIO4- Luminol体系化学发光有强烈的增敏作用, 结合反向流动注射技术, 首次建立了测定五氟利多的流动注射化学发光的方法; 在优化的实验条件下, 测定五氟利多的线性范围为 4.0× 10- 8~ 1.0× 10- 5 g/mL, 检出限为 9.2× 10- 9 g/mL, 对 4.0× 10- 7 g/mL的五氟利多进行 11次平行测定, 方法的相对标准偏差为 2.1%; 该法用于片剂五氟利多的含量测定, 结果满意. 相似文献
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基于Mn(Ⅱ) 邻菲罗啉对鲁米诺 KIO4化学发光体系的催化作用建立了测定Mn(Ⅱ)的分析方法。Mn(Ⅱ)质量浓度在2.0×10-6~5.0×10-5mg/mL范围与发光强度呈线性响应,回归方程为ICL=0.6+1.39×106ρ(mg/mL),检出限为2.0×10-6mg/mL。Cr3+、Fe2+、Co2+、Au3+等离子有干扰,使用EDTA、F-、8 羟基喹啉等为掩蔽剂可消除或降低干扰。将该法应用于生物化工产品丙酸钙、动物蛋白粉等中痕量锰的测定,加标回收率98%~102%,10次测定RSD为4 6%。将测定的结果与原子吸收法比较,相对偏差≤±3%。 相似文献
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鲁米诺-AuCl4^- -H2O2体系化学发光反应的研究——-矿石中痕量金的测定 总被引:13,自引:0,他引:13
液相化学发光分析法是一种灵敏度很高的分析方法。有人曾用此法以测定痕量金,检测极限1×10~(-8)g/mL金,工作曲线的线性范围1×10~(-8)~1×10~(-7)g/mL金。本文首次提出并用自制液相化学发光分析仪(图1)研究了鲁米诺-AuCl_4~--H_2O_2液相化学发光体系,确定了用这一体系测定金的最佳条件,制定了测定的具体方法。检测极限4×10~(-11)g/mL金,工作曲线的线性范围1×10~(-10)~1×10~(-5)g/mL金,相对标准偏差 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products. 相似文献
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《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献