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1.
用卡尔曼滤波-分光光度法测定无机铬的形态   总被引:18,自引:2,他引:16  
李方  李艳廷 《分析化学》2000,28(8):989-992
利用Kalman滤波技术和二溴苯基荧光酮-溴化十六烷基三甲基铵-C_2H_5OH分光光度测定体系,同时对Cr(Ⅲ)和Cr(Ⅳ)进行测定。Cr(Ⅲ)的表观摩尔吸光系数为1.96 × 10~5 L· mol~(-1)·cm~(-1),线性范围为0~ 4.0 x10-6mol/L;Cr(Ⅵ)的表观摩尔吸光系数为4.16 ×10~5L· mol~(-1)· cm~(-1),线性范围为0~5.2×10~(-1)mol/L。  相似文献   

2.
报道了一种磺苄青霉素药物电极,以十六烷基三辛基碘化铵为载体,用邻苯二甲酸二壬酯为增塑剂,运用序贯淘汰水平法对膜组成进行了优化;确定了电极最佳膜组成,讨论了一些因素对电极性能的影响。电极响应快速,选择性、稳定性、重现性均较好。电极检测下限可达1.66×10^-6mol/L,线性范围为6.03×10^-6~1.0×10^-1mol/L,斜率为28.0mV/pC,回收率为96.1%~100.4%。可用…  相似文献   

3.
在0.06mol/L柠檬醚钠-0.003mol/LHC1(pH6.5)介质中,2,3,4-三羟基-4′-磺基-偶氮苯和铋产生灵敏的单扫描极谱导数峰,铋含量在0~6.7×10 ̄(-6)mol/L范围内与波高成线性关系,检测限2.4×10 ̄(-8)mol/L。用提出的方法测定了锡中的铋,并对反应机理进行了研究。  相似文献   

4.
用循环伏安法研究了制备掺杂磷钼根离子聚吡咯化学修饰电极的条件,对其性能进行了电化学表征,电极对磷钼酸根(PMo12O^3-40)离子具有选择性电位响应,线性范围为1.0×10^-6~1.0×10^-3mol/L。斜率约为50mV,测定了电极的有关性能参数。电极可用于无机磷含量的检测。  相似文献   

5.
研究了Os(Ⅱ)和4,4’二(二乙氨基)苯硫酮与Pt(Ⅱ)共显色所衍生的配合物,于NucleosilC_8柱上,用含3×10 ̄(-3)mol/LDL-樟脑-10-磺酸和0.02mol/LHAc-NaAc(pH3.5)的乙腈-丙酮-水(72:5:23,V/V)作流动相(1.0mL/min)分离并检测。线性范围为0.2~4.0μg/mLPt;检测限为1.0ngPt。此方法已应用于抗癌药物顺铂和卡铂的分析。  相似文献   

6.
以四磺基铁酞菁(FeTSPe)作为过氧化物模拟酶催化H2O2与L-酪氨酸的荧光反应,建立了测定宽含量范围的H2O2及葡萄糖的方法。该法的线性范围为0.0-8.0×10^5mol/L,H2O2及0.0 ̄2.0×10^-4mol/L葡萄糖,检测限分别为5.0×10^-8mol/L及6.0×10^-6mol/L,将该经酶催化反应偶联,测定人血清中葡萄糖的含量,取得了满意的结果。  相似文献   

7.
催化动力学光度法测定痕量苯酚   总被引:5,自引:0,他引:5  
研究了在硫酸介质中苯酚对I^-1催化Ce^4+-As(Ⅲ)反应的抑制作用及其动力学条件。建立了用催化动力这光度法测定痕量苯酚的新方法,结果表明,在0.001mol/LCe(SO4)2,0.00125mol/L,As2O3,0.01mg/L,KI,0.0125mol/L,H2SO4和0.13%(w/v)NaCl溶液中测定苯酚,其表面摩尔吸光系数为2.1×10^5L.mol^-1.cm^-1,线性范围  相似文献   

8.
一种简单的葡萄糖测定方法   总被引:5,自引:0,他引:5  
韦寿莲  邓光辉 《分析化学》2001,29(4):425-427
报道了一种新的葡萄糖测定方法。它是基于可逆的光诱导电子转移过程,从而实现葡萄糖的快速测定。荧光染料(3-〔5-(4-二甲氨基苯基)-4,5-二氢唑-2-苯磺酰氨基〕苯硼酸)被首次应用于体液中葡萄糖的直接测定。方法的线性范围为0~1×10-2 mol/L,检测限为5×10-5 mol/L。用建立的方法对3个血清样品中葡萄糖的直接测定,结果满意,相对标准偏差小于4%。  相似文献   

9.
熊国华  刘虹 《分析化学》1994,22(11):1141-1144
本研究了Mn^2+和Co^2+对7-(8-羟基-3,6-二磺基萘偶氮)-8-羟基喹啉-5-磺酸-硼砂反应体系的混合荧光增敏作用。实验条件下,荧光增敏强度满足线性加和关系的范围是:Mn^2+浓度0 ̄2.9×10^-7mol/L;Co^2+浓度0 ̄8.8~10^-7mol/L;总浓度不超过1.0×10^-6mol/L。检出限量为Mn^2+4.5×10^-9mol/L和Co^2+1.4×10^-8mo  相似文献   

10.
在0.06mol/L柠檬酸钠-0.003mol/L HCl(pH6.5)介质中,2,3,4-三羟基-4'-磺基-偶氮苯和铋产生灵敏的单扫描极谱导数峰,铋含量在0~6.7×10^-6mol/L范围内与波高成线性关系,检测限2.4×10^-8mol/L。用提出的方法测定了锡中的铋,并对反应机理进行了研究。  相似文献   

11.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

12.
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   

13.
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   

14.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

15.
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   

16.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

17.
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.  相似文献   

18.
Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.  相似文献   

19.
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   

20.
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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