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1.
用1,5-二(2-羟基-5-磺基苯基)-3-氰基甲(月朁)(HSPCF)光度测定锌已有报导。实验发现,本实验室新合成的1,5-二(2-羟基-5-氯苯基)-3-氰基甲(月朁)(HCPCF)配合非离子表面活性剂使用,性能较HSPCF为佳:对比度由110nm增至140nm;摩尔吸光系数由2.09×10~4增至3.20×10~4。为进一步改善灵敏度以测定ppb数量级锌含量,可采用非离子表面活性剂浊点析相法。用聚氧乙烯壬基苯基醚-7.5,在室温下析相富集Zn-PAN络合物,可测定每2克试液中0.1—3.0μg锌。我们试验利用HCPCF及Triton X-100与锌的反  相似文献   

2.
对于水中低至10~(-7)~10~(-8)M的痕量Mn采用催化动力学光度分析法可获较佳灵敏度.本实验室合成的1,5-二(2-羟基-5-氯苯基)-3-氰基甲(月朁)(简称HCPCF)于氨性介质中在溶氧作用下为痕量Mn(Ⅱ)催化褪色.这一反应可能应用于痕量Mn(Ⅱ)的测定.文献中报道Mn(Ⅱ)的催化光度测定方法颇多,较近的工作已收入有关综述及专著,但对有关反应动力学及反应历程研究仍较少.本文试以Mn(Ⅱ)催化的HCPCF氧化反应为对象,对此进行初步探讨.  相似文献   

3.
研究了显色剂1,5-二(2-羟基-5-氯苯)-3-氰基甲(月替)(HCPCF)光度法同时测定锌和铜的方法.分别在pH 7.0乙酸铵和pH 3.6乙酸-乙酸钠介质中,Triton X-100存在下,锌和铜与HCPCF分别形成稳定的1∶1蓝色络合物,最大吸收波长分别为645nm和620nm,表观摩尔吸光系数分别为3.16×104L·mol-1·cm-1和3.10×104L·mol-1·cm-1,在0~30μg/25ml浓度范围内均符合比耳定律.可直接用于药物中微量锌和铜的测定.方法准确、快速、简便.  相似文献   

4.
合成了新试剂1,5-二(2-羟基-5-溴苯)-3-氰基甲月替(HBPCF),并研究了它与锌的显色反应。在pH9.5的氨-NH  相似文献   

5.
本文研究了1-(α-吡啶基)-5-苯基-3-(α-呋喃基)甲(月朁)的合成方法及其在非离子表面活性剂吐温-80存在下与镉的显色反应。在pH 9.5~12.0时,络合物的λ_(max)=654nm,δ_(654)=6.0×10~4。组成为Cd∶R=1∶2。镉含量在0—13微克/10毫升范围内服从比尔  相似文献   

6.
以对羟基苯腈和1,5-二溴戊烷为起始原料合成了1,5-二-(4-氰基苯氧基)戊烷(2);2在甲醇钠催化下制得1,5-二-[4-(甲亚胺酸甲酯)苯氧基]戊烷(3);3在饱和氨-甲醇溶液中氨解合成了喷他脒,总收率37.7%,其结构经1H NMR, IR和MS表征.  相似文献   

7.
催化动力学光度法测定痕量铁的研究   总被引:3,自引:0,他引:3  
在2,2′ 联吡啶的活化下,铁(Ⅲ)可催化过氧化氢氧化1,5 二(2 羟基 5 磺酸基苯) 3 氰基甲月替的反应;在最佳条件下,建立了测定痕量铁(Ⅲ)的方法,其检出限是1.96×10-12g/mL。方法用于水样和生物试样中痕量铁的测定,结果满意。  相似文献   

8.
HCPCF褪色光度法测定微量氧化性阴离子   总被引:1,自引:0,他引:1  
报道了l,5-二(2-羟基-5-氯苯)-3-氰基甲Ti(HCPCF)在酸性介质中与氧化性阴离子的反应。氧化性阴离子将HCPCF的四氮基转化为无色氧化型而使红色逐渐减褪。利用此褪色反应,探讨了测定NO2^-、BrO3^-、IO3^-、IO4^-、Cr2O7^2-的条件,其表观摩尔吸光系数达l0^4数量级,提出了测定氧化性阴离子的新方法。可用来测定饮用水、池塘水、废水、化学试剂、碘盐及海带中一些氧化性阴离子的含量。  相似文献   

9.
合成了新型1,7-双(N-取代氨基甲基)-2,8-二羟基-朝格尔碱(4),以4为催化剂催化了4-羟基香豆素和2-亚苄基丙二腈[或甲基(乙基)-2-氰基-3-苯基丙烯酸]的Aldol反应,获得了一系列化合物8;以4为配体与钯联合催化了串联Aldol-Ullmann反应,得到了化合物10和12.测试了所有化合物对人三阳性乳腺癌细胞(MCF-7)、人三阴性乳腺癌细胞(MDA-MB-231)、人肝癌细胞(HepG2)和人肝癌细胞(MHCC-97H)的抗癌活性以及对人肝细胞(LO2)的细胞毒性.其中,1,7-双((甲基氨基)甲基)-6H,12H-5,11-甲二苯并[b,f][1,5]二氮芳辛-2,8-二醇(4b)对MCF-7(抑制率>30%)、1,7-双((((1-苯乙基)氨基)甲基)-6H,12H-5,11-甲二苯并[b,f][1,5]二氮芳辛-2,8-二醇(4d)和1,7-双(((吡啶-2-基甲基)氨基)甲基)-6H,12H-5,11-甲基二苯并[b,f][1,5]重氮-2,8-二醇(4e)对MDA-MB-231具有较高的选择性和抑制活性, 2-氨基-5-氧代-4-(3,4,5-三甲氧...  相似文献   

10.
研究了硫酸介质中,CTMAB存在下,亚硝酸根氧化1,5-二(2-羟基-5-溴苯)-3-氰基甲月替(HBPCF)褪色反应,据此建立了测定微量亚硝酸根的新方法。λmax=520 nm,表观摩尔吸光系数为3.1×104L.mol-1.cm-1,线性范围为0~2.1μg/mL。用于水样中亚硝酸根的测定,结果满意。  相似文献   

11.
非离子表面活性剂在胶束增溶分光光度法中的作用(Ⅱ)   总被引:1,自引:0,他引:1  
本文以乳化剂OP对结晶紫及结晶紫-磷钼杂多酸缔合物的作用为代表,研究了非离子表面活性剂与碱性染料显色体系的相互作用,提出了非离子表面活性剂起增溶作用的第二种模式--拟均相萃取模式,并用浊点析相分离法进行了验证。  相似文献   

12.
The microsurface adsorption-spectral correction technique (MSASC) has been applied to investigation of the ternary interaction of 1,5-di(2-hydroxy-5-sulfophenyl)-3-cyanoformazan (DHSPCF) with cetyltrimethylammonium bromide (CTAB) and rare earths Y, Eu, Dy and Yb. The CTAB micelle enriched DHSPCF molecules on its microsurface in monolayers and then sensitized the complexation between rare earths and DHSPCF. The binary aggregate and the ternary complex both were characterized.  相似文献   

13.
Ion-association extraction of some aromatic sulfonate ions including alkylbenzene sulfonates with tetrabutylammonium ion (TBA+) into nonionic surfactant micelle has been investigated through the changes in the electrophoretic mobility. Nonionic surfactants of Brij 35 and Brij 58 were used as micelle substrates to which the ion-associates formed could distribute. The electrophoretic mobility of the aromatic sulfonate ions was measured by capillary zone electrophoresis in the presence of TBA+ and/or the nonionic surfactant to determine ion-association constants (K(ass)), binding constants of the anions to the nonionic surfactant micelle (K(B)), and binding constants of the ion-associates to the nonionic surfactant micelle (K(B,IA)). Nonlinear phenomena induced with the alkyl chain moiety were observed on K(ass) and K(B) by its linear structure and the mixed micelle formation, respectively. Larger K(B) values were obtained with Brij 58 as micelle matrix than with Brij 35, while the differences in K(B,IA) were small between Brij 58 and Brij 35.  相似文献   

14.
The critical micelle concentration of mixtures of anionic and nonionic surfactants was measured. The anionic surfactants were alkylbenzene sulfonates and the nonionic surfactants were polyoxyethylene nonylphenols and a polyoxy-ethylene alcohol. The effect of added electrolyte, the number of ethylene oxide units in the polyethoxylate, and the anionic alkyl chain length were studied. All systems showed substantial negative deviations (lower CMC) from ideal solution theory. The results can be represented by regular solution theory. Charge separation appears to be the source of the nonideality. This considers the reduction of electrostatic repulsion between the ionic surfactant head groups in the mixed micelle, due to the insertion of nonionic hydrophilic groups between these charged groups, to be the cause of enhanced micelle formation. The physical basis of regular solution theory was shown to be consistent with the charge separation effect.  相似文献   

15.
Nonionic surfactants have broad applications such as cleaning and dispersion stabilization, which frequently are hampered by strong temperature sensitivities. As manifested by clouding and decreased solubility with increasing temperature, the interaction between water and the oligo(oxyethylene) head-groups is becoming less favorable. Different aspects of surfactant self-assembly, like the critical micelle concentration, micelle size and shape, intermicellar interactions and phase separation phenomena are reviewed as well as suggested underlying causes of the temperature dependence. Furthermore, the effect of cosolutes on clouding and the behavior of related systems, non-aqueous solutions and nonionic polymers, are examined.  相似文献   

16.
俞汝勤  曾鸽呜  林润国 《化学学报》1983,41(10):960-965
The aerial oxidation of 1, 5-bis (2-hydroxy-5-chlorophenyl)- 3-cyanoformazan (HCPCF) in ammoniacal medium catalyzed by Mn(II) has been investigated and used for spectrophotometric determination of trace Mn(II) in water. The effect of various experimental factors was studied and the optimal conditions for Mn(II) determination were found. It has been shown that the reaction follows the rate expression:  相似文献   

17.
两相催化体系中烯烃氢甲酰化的高区域选择性   总被引:1,自引:0,他引:1  
采用水溶性铑膦配合物催化剂在两相(水/有机物)体系中进行长链烯烃氢甲酰化反应合成高碳醛,具有反应条件缓和、催化剂与产物容易分离的优点,而且用水作溶剂既便宜、又安全,有利于环境保护,因此引起国内外化学家重视,进行了大量研究[1,2].  相似文献   

18.
The polymerization of acrylamide in micellar solutions of cationic, anionic, zwitterionic and nonionic surfactants, initiated by NaHSO3, has been studied at 20 and 30° C with time variable method of thermokinetics for the 1. 5-order reaction in this paper. Reaction mechanism has been suggested and rate equations have been derived. The results indicate that ionic (CTAB, TTABDTAB, SDS) and zwitterionic (SLS) surfactants catalyze the polymerization in the order SDS>SLS>DTAB ≈ TTA≈ CTAB, and nonionic surfactant (Brij35) has slight inhibition effect. These effects are mainly caused by the effect of the formation of micelle- HSO3 complex on the step of initiator to form free radical.  相似文献   

19.
The self-assembly of the protein hydrophobin, HFBII, and its self-assembly with cationic, anionic, and nonionic surfactants hexadecylterimethyl ammonium bromide, CTAB, sodium dodecyl sulfate, SDS, and hexaethylene monododecyl ether, C(12)E(6), in aqueous solution have been studied by small-angle neutron scattering, SANS. HFBII self-assembles in solution as small globular aggregates, consistent with the formation of trimers or tetramers. Its self-assembly is not substantially affected by the pH or electrolytes. In the presence of CTAB, SDS, or C(12)E(6), HFBII/surfactant complexes are formed. The structure of the HFBII/surfactant complexes has been identified using contrast variation and is in the form of HFBII molecules bound to the outer surface of globular surfactant micelles. The binding of HFBII decreases the surfactant micelle aggregation number for increasing HFBII concentration in solution, and the number of hydrophobin molecules bound/micelle increases.  相似文献   

20.

The physicochemical properties of initial formulation, that is anionic/amphoteric surfactants mixture SLES/AOS/CAB (sodium lauryl ether sulfate (SLES), α-olefin sulfonates (AOS) and cocamidopropyl betaine (CAB) at ratio 80 : 15 : 5) with nonionic surfactant of amine oxide type (lauramine oxide (AO)) in various concentration (1–5%) were studied. To characterize the surfactants mixture, the critical micelle concentration (CMC), surface tension (γ), foam volume, biodegradability and irritability were determined. This study showed that adding of AO in those mixtures lowered both γ and CMC as well as enhanced SLES/AOS/CAB foaming properties, but did not significantly affect biodegradability and irritability of initial formulation. Moreover, an increase in AO concentration has a meaningful synergistic effect on the initial formulation properties. All those results indicates that a nonionic surfactant of amine oxide type significantly improves the performance of anionic/amphoteric mixed micelle systems, and because of that anionic/amphoteric/nonionic mixture can be used in considerably lower concentrations as a cleaning formulation.

  相似文献   

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