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1.
In this paper, the ion transfer process of bromocresol purple(BCP) across the liquid/liquid interface has been described. The effects of the supporting eletrolyte in two phases and solvent on the transfer behavior of bromocresol purple have been investigated in detail and the relationship between the ion transfer and concentration of electrolytes in the organic phase is explained in terms of the dissociation of TBA~+ anti TPB~- in the organic phase. The proposed transfer mechanism for BCP has been proved to be reasonable by UV-spectroscopy of the products of the electrolysis in aqueous phase. The standard potential differences △_0~wφ~0 and standard Gibbs energies △_0~WG~0 of BCP transfer from water to some organic solvents are calculated. The dissociation constants of BCP obtained are in agreement with the literature values.  相似文献   

2.
季铵酚离子在水/硝基苯界面的转移   总被引:1,自引:0,他引:1  
油/水界面上的电化学研究是近年来电化学研究中的一个新领域,对膜电化学的发展具有重要意义。目前研究油/水界面电化学中普遍使用循环伏安(CV)法和循环线扫电流计时电位(CLC)法。有关抗生素在油/水界面的转移已有报导,本文用CLC法和CV法对肌肉松弛剂季铵酚离子在水/硝基苯界面的转移行为进行了研究。 所用三碘季铵酚为中国科学院生物化学研究所生产的化学试剂,其他试剂及仪器均与前文相同  相似文献   

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The transfer phenomena of quinine drug at the aqueous 1,2- dichloroethane (DCE)interface have been studied by the current- scanning polarography. The relationships be-tween the wave height and pH of aqueous phase, concentration of quinine as well as therate of water drop are discussed. The effect of supporting electrolyte, buffer solution andthe nature of organic solvent on the polarographic wave is studied. The transfer char-acteristics of quinine in aqueous phase and in organic phase are compared, The mono- pro-tonated and diprotonated quinines can both transfer at the interface so as to produce twopolarographic waves. The transfer process of quinine at the interface is simultaneouslycontrolled by diffusion and reestablishment of the disturbed protonated equilibrium ofquinine. A further investigation is made by chronopotentiometry. On the basis of thetheoretical analysis, the formulae of the limiting current are derived and discussed. Thetheoretical results are in agreement with the experimental ones.  相似文献   

7.
基于乙酸铜与单宁生成沉淀,铜离子在NH3-NHCl介质中能产生灵敏的极谱波,利用线性扫描极谱法测定剩余铜离子,建立了间接测定中药中单宁的新方法。测定单宁的线性范围为2.0—12.0ug/mL.检出限为1.1ug/mL。该方法应用于中药五倍子、诃子中单宁的测定,测定结果的相对标准偏差小于5%(n=4),回收率为97.1%-101.5%。  相似文献   

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端烯基液晶冠醚推动钠离子在微液/液界面的转移   总被引:1,自引:0,他引:1  
用循环伏安法研究新型载体端烯基液晶冠醚推动钠离子的转移,结果表明,钠离子的转移由扩散控制.探讨了影响钠离子转移的因素,如端烯基液晶冠醚和钠离子的浓度等.求算出端烯基液晶冠醚在1,2-二氯乙烷中的扩散系数为(2.61±0.12)×10-6cm2/s,端烯基液晶冠醚和钠离子在1,2-二氯乙烷中所形成的配合物稳定常数lgβo=5.7.  相似文献   

9.
报道了一种用于偏氟乙烯-三氟氯乙烯共聚物(VDF/CTFE共聚物)制备偏氟乙烯/三氟乙烯/三氟氯乙烯共聚物(VDF/TrFE/CTFE共聚物)的新方法,该方法以CuCl与2′,2-Bpy的配合物为催化剂,N-甲基吡咯烷酮(NMP)为溶剂,异丙苯(丙酮、2,6-二叔丁基-4-甲基苯酚)为链转移剂,通过原子转移法在VDF/CTFE共聚物上产生自由基,进而利用自由基链转移反应将VDF/CTFE共聚物上部分Cl原子用H原子取代以制备VDF/TrFE/CTFE三元共聚物.对该体系的反应机理及其影响因素进行研究发现,随着实验温度的升高(80~140℃),反应时间的延长,氢化量增加,产物中TrFE含量增加;反应温度越高,初始反应速度越快,完全氢化时间越短;催化剂与氢化量的比例基本为1:1,通过控制催化剂的量可以定量控制氢化率;新的反应体系不会对产物的分子量产生大的影响.  相似文献   

10.
铈离子与氨基甲酸酯类化合物引发丙烯酰胺聚合的研究   总被引:2,自引:1,他引:2  
本文对铈离子与苯基氨基甲酸酯类化合物在H_2O-CH_3CN(3∶1,V/V)及H_2O-HCONH_2(1∶2,V/V)两种介质中引发丙烯酰胺的聚合进行了研究。考察了不同结构的苯基氨基甲酸酯对聚合的影响。苯基氨基甲酸酯类化合物对铈离子引发聚合均有促进作用,其中对-甲苯基氨基甲酸酯的促进作用最为显著。测定了聚合反应表现活化能及聚合动力学方程,并提出了聚合反应机理。  相似文献   

11.
(NBR/PVC)/CuSO_4复合材料中配位交联反应的研究   总被引:1,自引:0,他引:1  
采用差示扫描量热法(DSC)和傅立叶转换红外光谱(FT-IR)对丁腈橡胶/聚氯乙烯合金/无水硫酸铜((NBR/PVC)/CuSO4)混合物的配位交联反应进行了研究.结果表明,(NBR/PVC)/CuSO4共混物在升温过程中出现两个放热峰,分别归因于腈基(—CN)和CuSO4之间的配位交联反应和体系中NBR/PVC的自交联反应.通过对共混物配位交联反应动力学参数的计算发现,混合物中CuSO4含量的多少并未对体系配位交联反应的进行产生影响.同时共混物中PVC的存在促进了配位交联反应的进行,降低了铜离子(Cu2+)与—CN之间配位交联反应的表观活化能Ea.  相似文献   

12.
Pt/Al2O3蜂窝状催化剂上NO选择性催化还原反应动力学研究   总被引:3,自引:0,他引:3  
采用多次涂层和浸渍法制备了蜂窝状Pt/Al2O3催化剂,并在高空速和大气体流量条件下对无梯度循环式反应器和积分反应器上催化剂的活性进行了比较。同时采用循环式反应器对动力学数据进行了测定。根据Langmuir-Hinshelwood模型和实验结果,推测了NO-C3H6-O2体系的SCR反应机理,并导出了NO和C3H6反应速率的数学表达式。据此所计算的理论模拟值能够与实验值很好地吻合。实验结果表明,氧气浓度对NO和C3H6的反应速率有明显的影响,二者均随着氧浓度c (O2)的增加达到峰值,再增加氧气浓度时,C3H6的反应速率r(C3H6)保持不变,而NO反应速率r (NO)却下降,而且下降的程度随着温度的升高而加剧。同时,随着氧气浓度增加,r (NO)达到最大值时的温度亦随之下降。  相似文献   

13.
利用N,O-双三甲基硅基三氟乙酰胺(BSTFA)和三甲基氯硅烷(TMCS)衍生化试剂对乳粉中三聚氰胺进行衍生化处理,利用离子阱气相色谱质谱联用仪,建立了全扫描、选择离子监测、二级质谱3种测定三聚氰胺的质谱方法.选择离子监测以三聚氰胺衍生物的特征离子m/z342,327,171,99为定性离子,以m/z327为定量离子;全扫描法二级质谱特征峰为定性依据,以特征离子m/z327为定量离子;二级质谱法以衍生物二级质谱m/z285,171,213为定性离子,以m/z 285为定量离子.3种方法的线性范围为0.05~2.0 mg/L,线性相关系数分别为0.9986、0.9990、0.9988;检测限分别为0.005、0.002、0.003 mg/kg,RSD分别为6.3%、5.7%、6.1%(n=6),方法的回收率为84%~105%.3种不同质谱检测方法应用到乳粉的检测中效果良好,均能够满足乳粉中三聚氰胺的检测要求.  相似文献   

14.
New liquid crystalline monomer, 2,5-bis[(4'-methoxyphenoxy)carbonyl]phenyl acrylate wassuccessfully synthesized. Polyacrylate with laterally attached mesogens via ester linkage was also derived.This polymer forms an enantiotropic liquid crystal phase while its monomer exhibits a metastable nematicphase with respect to the crystalline state. However, its liquid crystallinity is very low as compared to that ofpoly{2,5-bis[(4'-methoxyphenoxy)carbonyl]-styrene}.  相似文献   

15.
生物碱类药物的液/液界面电化学研究   总被引:4,自引:0,他引:4  
俞泽穆  李楠 《分析化学》1992,20(9):1032-1036
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16.
用循环线性电流扫描计时电位法和循环伏安法研究了双1∶11镝的硅钼杂多酸阴离子在水/硝基苯界面的转移。在pH=1.1~5.3时,转移离子为H9Dy(SiMo11O39)24-.根据循环伏安结果计算得转移离子的标准电位差和Gibbs转移自由能分别为0.102V和-39.5kJ•ml-1,并由循环线性电流扫描计时电位法计算了转移离子的有关动力学参数,H9Dy(SiMo11O39)24-在水/硝基苯界面的转移属准可逆转移.  相似文献   

17.
《Electroanalysis》2004,16(12):1014-1018
The transfer of sodium cation facilitated by (anthraquinone‐1‐yloxy) methane‐15‐crown‐5 (L) has been investigated at the water/1,2‐dichloroethane microinterface supported at the tip of a micropipette. The diffusion coefficient of (anthraquinone‐1‐yloxy) methane‐15‐crown‐5 obtained was (3.42±0.20)×10?6 cm2 s?1. The steady‐state voltammograms were observed for forward and backward scans due to sodium ion transfer facilitated by L with 1 : 1 stoichiometry. The mechanism corresponded to an interfacial complexation (TIC) and interfacial dissociation (TID) process. The association constant was calculated to be log βo=11.08±0.03 in the DCE phase. The association constant of other alkali metals (Li+, K+, Rb+) were also obtained.  相似文献   

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