首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
本文详细研究了乙基罗丹明B-磷钼杂多酸-PVA超高灵敏显色反应,提出了高灵敏测量痕量磷的新的分光光度法。缔合物的最大吸收波长位于584nm处,其表观摩尔吸光系数为1.3×10^6mol^-1.cm^-1。并研究了缔合物的组成和红外光谱,本法直接用于钢样及试剂中痕量磷的测定,获得满意的结果,检测下限达6×10^-7%。  相似文献   

2.
在0.2mol·L ̄(-1)NH_4Cl-NH_3·H_2O底液中,(pH为9.26),得到一个极为灵敏的Fe(Ⅲ)-TEA-5-Br-PADAP-H_2O_2配合吸附催化波,其峰电位为-0.71V(vs.SCE)。铁浓度在1.8×10 ̄(-10)~5.4×10 ̄(-6)mol·L ̄(-1)范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究,证明是一种配合吸附催化波,并成功地应用于各类水样,钒催化剂中微量或痕量铁的测定。  相似文献   

3.
本文采用装有Jones柱的流动注射系统,研究了钒(Ⅱ)-光泽精体系的化学发光反应。在此基础上建立了痕量钒测定的新方法。方法的检出限3×10 ̄(-10)g·mL ̄(-1);对于1.0×10 ̄(-7)g·mL ̄(-1)钒标准溶液测定的相对标准偏差为2%(n=11);线性范围1.0×10 ̄(-9)~9.0×10 ̄(-5)g·mL ̄(-1),相关系数大于0.9980。该方法已用于水样中痕量钒的测定。对于反应机理,本文也进行了探讨。  相似文献   

4.
本文研究了溴化十二烷基二甲基苄基铵-溴百里酚蓝与阴离子表面活性剂显色反应的适宜条件。结果表明,在pH7.4~8.2范围内阴离子表面活性剂与题示试剂形成1:2:1的绿色离子缔合物,其最大吸收峰位于614nm处。表现摩尔吸光系数分别为:=3.99×10 ̄4L·mol ̄(-1)·cm ̄(-1);=3.70×10 ̄4L·mol ̄(-1)·cm ̄(-1);=1.71×10 ̄4L·mol ̄(-1)·cm ̄(-1)。SDBS在0~195μg/10mL,SDS在0~158μg/10mL,SLS在0~60μg/10mL范围内遵守比耳定律。该法用于河水和生活废水中阴离子表面活性剂测定,结果满意。  相似文献   

5.
在聚乙烯醇存在下,钌与铜酸盐和耐尔蓝(NB)形成离子缔合物,缔合物的λ_(max)为585nm,ε为1.32×10 ̄6L·mol·cm ̄(-1),符合比耳定律范围0~1.2μg/25mLRu,检测限为2.6ng/mL(n=11),用平衡移动法测定缔合物的摩尔比为Ru:NB=1:2。考察了43种共存离子的影响,仅O_s(Ⅲ)、、As(Ⅲ)、Sb(Ⅲ)、Ge(Ⅳ)有干扰,需用蒸馏分离。本法已用于某些岩矿和冶金产品中钌的测定,结果满意。  相似文献   

6.
在一定的酸度条件下,结晶紫与磷钼杂多酸离子缔合物的流动注射分光光度法可直接测定痕量磷。灵敏度高,重现性和选择性好。水中常见离子不干扰痕量磷的测定,工作曲线的线性范围为0 ̄500μg·L^-1的磷,检出下限达1.0μg·L^-1,以120h^-1采样频率,对各种天然水样进行测定,回收率为92.5% ̄105.0%,相对标准偏差为0.1% ̄6.7%。  相似文献   

7.
PNPAR-CTMAB光度法测定水中痕量阴离子表面活性剂   总被引:2,自引:0,他引:2  
本文研究了对硝基偶氮间苯二酚(PNPAR)与溴化十六烷基三甲铵(CTMAB)形成的离子缔合物PNPAR-CTMAB作显色剂与阴离子表面活性剂(AS)的显色反应。发现在pH13.0的NaOH介质中,AS能定量置换出PNPAR-CTMAB中的PNPAR,而使其最大吸收波长630nm处吸光度下降。阴离子表面活性剂十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)的ε值分别为3.5×10 ̄4,5.8×10 ̄4L·mol ̄(-1)·cm ̄(-1),浓度分别在0~87μg/25mL,0~68μg/25mL范围内符合比尔定律。此法应用于环境水中痕量阴离子表面活性剂测定,结果满意。  相似文献   

8.
本文利用流动注射系统研究了由Jones柱产生的铀(Ⅲ)与鲁米诺之间的化学发光反应,建立了痕量铀的化学发光测定法。方法的检出限是3×10 ̄(-10)g/mL铀。校准曲线的线性范围是1×10 ̄(-9)~4×10 ̄(-6)g/mL铀,相对标准偏差为2%(测定2×10 ̄(-9)g/mL铀,n=11)。对于反应机理进行了初步研究。  相似文献   

9.
本文较详细研究了在H_2SO_4介质中,Ti(Ⅳ)-F ̄--o-NPF-CPC体系水相光度法测定痕量钛的新方法。四元体系的最大吸收峰在565nm处,表观摩尔吸光系数为2.1×10 ̄5L·mol ̄(-1)·cm ̄(-1),Sandell灵敏度为2.28×10 ̄(-4)μgTi/cm ̄2。钛含量在0~4μg/25mL范围内遵守比尔定律。方法用于土壤、粮食、牧草、蔬菜和中草药中钛的测定,结果满意。  相似文献   

10.
在pH5.1的HCl-六次甲基四胺缓冲溶液中,Cd(Ⅱ)-β-巯基丙酸配合物产生-灵敏的极谱吸附波.峰电流在-0.67V(vs.SCE)左右,峰高与镉浓度在1.8×10-9~3.6×10-6mol/L范围内呈线性关系.检出限为9×10-10mol/L.研究了极谱波的性质和电极过程机理.本法用于食品中痕量镉的测定,结果满意  相似文献   

11.
HEPT类化合物的QSAR研究   总被引:3,自引:0,他引:3  
章文军  许禄 《应用化学》2001,18(9):717-0
为定量结构/活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法(Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物(1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构/活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。  相似文献   

12.
Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.  相似文献   

13.
通过在LS55型荧光-磷光-发光分光光度计上加装液滴产生及调节附件,采用计算机采集与分析处理数据,成功地研制了双通道液滴光化学传感装置.利用葡聚糖凝胶对复合维生素B中不同组分的选择性吸附来达到分离与同时检测的目的,并将其用于复合维生素B药片的分析,取得了满意的结果.  相似文献   

14.
The content of the fine and ultrafine particles in the raw material results in difficulty of the separation, the loss of the valuable components and ecological contamination. Secondary using of the fine particles is impossible without their granulation. This problem has been solved by the agglomeration-in-liquid method.An agglomeration-in-liquid method is a process to produce agglomerates in a liquid phase from solid particles suspended in the liquid. The surface of solid particles and the binding liquid must be of identical polarity, but the continuous phase must be of the opposite polarity. The water solutions of the surfactant are the binding liquids or the organic liquids.  相似文献   

15.
Similarity of the extrusion curves of non-wetting liquid in a nanoporous medium with different initial fill volume fractions is observed experimentally. The similarity can be explained by the scaling of the interface energy and the self-similarity of the infinite percolation cluster of fluid-filled pores. Understanding the physical processes leading to the observed phenomena is a foundation for the development of high-performance devices for damping and energy storage on the basis of such heterogeneous systems.  相似文献   

16.
The synthesis and liquid crystalline behaviour of the first and second generations of a dendrimeric structure based on poly(propyleneimine)(DAB-dendr(NH2)x) are reported. 4-(4-n-Alkoxybenzoyloxy)salicylaldehydes are used as mesogenic moieties attached at the peripheral amino groups of the dendrimers giving rise to dendromesogens with four and eight mesogenic branches. From these dendromesogens, considered as organic ligands, were prepared six metal-containing dendrimers which incorporate two or four copper atoms in their structures. All the dendrimeric ligands and three of the metal-containing dendrimers exhibit liquid crystalline properties which were studied by optical microscopy, DSC, X-ray diffraction and EPR spectroscopy.  相似文献   

17.
An approximated hardness kernel, which includes the second derivative with respect to the density of the kinetic energy, the electron-electron coulomb repulsion, and the exchange density functionals, has been tested for the calculation of the global hardness. The results obtained for a series of 40 cations and neutral systems and 16 anions represent in most cases an improvement of the results obtained using the HOMO-LUMO gap approach and indicate the viability of this approach to evaluate global hardness. In addition, the relevance of the Fukui function approximation and the role of the three components of the hardness kernel in the evaluation of the global hardness have been analyzed.  相似文献   

18.
A new chromophore, C1 , based on a similar DπA‐structure as in the FTC ‐chromophore but with a hydroxyalkyl spacer perpendicular to the direction of the dipole moment was synthesized. Both chromophores and the CLD ‐chromophore were used to prepare high Tg nonlinear optical vinyl polymers. The influence of the position of the spacer on the DπA‐system on the NLO response of the resulting polymers was investigated.

  相似文献   


19.
20.
用电势阶跃法和旋转圆盘电极法 (RDE)以及SEM和XRD测试手段 ,初步研究了光亮剂对氰化体系中银电沉积行为的影响 .研究表明 ,光亮剂的加入并未导致银电沉积成核机理的改变 ,但显著增强了镀液的微观平整效应 ,并且所得镀层的表观光滑程度明显改善 .XRD测试亦同时表明光亮剂的加入并未改变镀层的择优取向  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号