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Kalman滤波-流动注射化学发光法同时测定痕量铌和钽的研究 总被引:3,自引:0,他引:3
流动注射化学发光(Flow injection-chemiluminescence,简称FI-CL)是基于流动注射(FI)进样技术与化学发光(CL)定量分析结合的痕量分析技术,具有仪器简单、操作方便及易于自动化等特点,从而在分析痕量元素方面取得了较大进展,尤其在痕量金属元素快速分析方面更具有优势. 相似文献
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基于硫普罗宁[化学名为N-(2-巯基丙酰基)-甘氨酸]对铁(Ⅲ)的还原反应和还原后的铁(Ⅱ)与邻菲啰啉的显色反应生成吸收峰在508nm处的络合物,并应用了流动注射技术,提出了间接测定硫普罗宁的流动注射光度分析法。设计并自制了流动注射分析仪,采用光栅分光光度计作为检测单元,此仪器的测定频率达到85次.h-1。硫普罗宁的质量浓度在4.00~450mg.L-1范围内与吸光度呈线性关系,检出限(3s/k)为0.56mg.L-1。应用此方法分析了硫普罗宁片剂及针剂样品,所得测定值与标准方法的测定值相符。以此两种样品为基体,加入标准溶液作回收试验,测得片剂及注射剂的回收率分别为100.5%及99.2%。 相似文献
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中成药中微量汞的流动注射-冷原子吸收测定方法研究 总被引:2,自引:0,他引:2
研究了流动注射氢化物发生-原子吸收光谱法测定微量汞时的最佳条件,建立了中成药中微量汞的流动注射.冷原子吸收光谱分析方法。测定中成药中汞的检出限为2.7×10-9,线性范围0-60μg·L-1,相对标准偏差小于5%,加标回收率为95%-98%。方法操作简便、快速、灵敏、自动化程度高,应用于实际中成药样品中微量汞的测定,结果满意。 相似文献
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提出了基于正硅酸与钼酸铵的显色反应和流动注射分析装置的流动注射光度法测定地热水中可溶性硅量的方法。对仪器的各项工作参数,包括显色反应所需钼酸铵溶液的浓度及要求的酸度条件,各反应圈的长度,试剂环的定量体积,流动注射系统出口的流量等做了试验并予以优化,所提出的装置可达到每小时60个样品的进样频率。测定二氧化硅的线性范围为20~800 mg.L-1。应用此法对实样的测定结果与国家标准方法(GB/T 12148-2006)测得的结果相符。 相似文献
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《理化检验(化学分册)》2021,(3)
以茶叶中常见的8种茶多酚化合物为研究对象,研究了三价银配合物[Ag(Ⅲ)]-鲁米诺流动注射化学发光法与2,2-联苯基-1-苦基肼基(DPPH)自由基清除法、邻苯三酚-碳酸盐-鲁米诺化学发光法和鲁米诺-过氧化氢化学发光法检测结果的相关性,并采用Ag(Ⅲ)-鲁米诺流动注射化学发光法评价了4种茶饮料的抗氧化活性。设置的仪器工作参数如下:载流为纯水,蠕动泵转速为25r·min~(-1),光电倍增管负高压为600V。结果发现:Ag(Ⅲ)-鲁米诺流动注射化学发光法所得化学发光强度差值与DPPH自由基清除法所得的IC_(50)(自由基清除率为50%时对应的抗氧化剂浓度)相关性较好,相关系数为0.949 0。方法用于市售4种茶饮料抗氧化性能评价,所得结果与DPPH自由基清除法一致,相关系数为0.966 5。 相似文献
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稀土分离流程中,需要能随时测定稀土含量而又简便的分析方法,离子选择电极可能适应这种需要。我们在稀土电极研究的基础上,研制了重稀土离子选择电极,并以该电极膜制成重稀土流通池,将其应用在流动注射分析中,可能是重稀土分析中较理想的方法之一。1 主要仪器和试剂 主要仪器有PW 9409酸度计(Philips),FlA-T_2通用流动注射仪(东北电力学院仪器仪 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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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 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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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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