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1.
本文以罗丹明B-酰肼和2-氯-3-喹啉醛经缩合反应得到新型的罗丹明B衍生物3,其结构经1H NMR,MS,元素分析表征.通过荧光光谱法研究了目标物3在CH3CN-H2O溶液中与金属离子的识别特性.结果表明:目标物3可作为荧光探针选择性识别Hg2+,识别过程是不可逆的.  相似文献   

2.
以罗丹明B和间氨基吡啶缩合反应得到新型罗丹明B衍生物L1,并用1H NMR,IR,HRMS-ESI及X射线对其结构进行了确证.通过荧光光谱法研究了目标物L1在水溶液中与金属离子的识别特性.结果表明目标物L1作为荧光探针可选择性的比色识别Fe3+,并且受常见离子的干扰较小.探针L1的荧光强度与Fe3+浓度(1×10-6~9×10-6 mol/L)呈较好的线性关系.  相似文献   

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本论文设计合成了基于1,3-二氨基胍盐酸盐、氨基胍盐酸盐的新型香豆素类荧光探针L1、L2。通过紫外-可见、荧光光谱的变化研究探针L1、L2对金属离子的识别效应。利用Job’s plot曲线确定探针L1与Co2+形成了1∶2的配合物,探针L2和Fe3+形成了3∶1的配合物,且表现为明显的荧光增强。探针L1对Co2+的检出限可达到10-6mol/L,探针L2对Fe3+的检出限可达到10-7mol/L。两种高灵敏度荧光探针有望应用于生物和环境监测领域。  相似文献   

4.
张华  刘爱红  吴芳英 《化学学报》2012,70(8):1001-1007
合成了2,4-二甲基-6-(4’-N,N-二甲氨基苯乙烯基)-1,3,5-均三嗪(1)和2-苯乙烯基-4,6-二甲基-1,3,5-均三嗪(2)两种化合物,并对其进行了1H NMR,MS,元素分析等表征.采用吸收光谱法研究了金属离子与化合物间的相互作用,结果显示:化合物1对Fe3+和Cu2+表现出高选择性光谱响应,其最大吸收波长由393 nm分别红移至525 nm和513 nm,溶液颜色由黄色变为粉红色.化合物1与Fe3+结合形成1∶1型配合物,其结合常数为1.8×104L mol-1;与Cu2+结合形成2∶1型配合物,其结合常数为2.6×1010L mol-1.化合物2仅对Fe3+呈现显著的光谱变化,其最大吸收波长由304nm红移至357 nm,而Cu2+的加入未引起光谱明显变化,2与Fe3+亦形成1∶1型配合物,结合常数为1.0×105L mol-1.结果表明Fe3+可能与化合物1和2中三嗪N配位,而Cu2+与化合物1中甲氨基中的N配位.同时考察了其它金属离子如Li+,K+,Mg2+,Ca2+,Co3+,Ni2+,Ag+,Cd2+,Hg2+和Zn2+等离子对化合物1和2吸收光谱的影响,结果显示两者光谱均无明显变化,据此提出了高选择性Fe3+,Cu2+的识别体系.  相似文献   

5.
设计合成了2种新型N-芳基香豆素甲基酮缩氨基硫脲受体分子S1和S2, 利用紫外-可见(UV-Vis)吸收光谱考察了其对Fe3+, Hg2+, Ag+, Ca2+, Cu2+, Zn2+, Pb2+, Cd2+, Ni2+, Cr3+和Mg2+等阳离子的识别作用. 结果表明, 当加入Cu2+时, 溶液颜色立刻由无色变为黄色, 而加入其它阳离子则无变化, 从而实现了对Cu2+的裸眼检测, 具有专一选择性比色识别效果. 通过计算可知, 受体分子S2对Cu2+的络合常数大于S1, 且主客体间形成1: 1的配合物. 受体分子S2对Cu2+的检出限为2.0×10-7 mol/L, 稳定常数Ks=1.02×105 L/mol. 另外, 在EDTA存在时, 配合物可以释放出Cu2+, 与EDTA结合, 表现出对Cu2+的"off-on"模式.  相似文献   

6.
以2-氨基酚和3-(二乙基氨基)苯酚为原料,经过5步反应合成了新型罗丹明类荧光探针化合物,研究发现该化合物对Ca2+具有较高的选择识别性能,并且受常见离子的干扰较小.探针的荧光强度与Ca2+浓度(2×10-6~5×10-5mol/L)呈较好的线性关系.  相似文献   

7.
以罗丹明B与邻苯二甲酰氯为原料缩合反应得到新化合物T1,通过荧光光谱法研究了化合物与金属离子的识别特性.结果表明荧光探针T1能对Hg2+进行快速、选择性、可逆的识别,且常见金属离子对其干扰较小.探针的荧光强度与Hg2+浓度(4×10-8~9×10-8 mol/L)呈现较好的线性关系.探针在HepG2活细胞中的荧光显微成像表明T1可应用于生物体的检测.  相似文献   

8.
合成并表征了一种荧光素衍生物——硫代异氰酸苯酯荧光素(FHBS);采用紫外-可见光谱和荧光光谱,在乙醇/4-羟乙基哌嗪乙磺酸(HEPES)(体积比1∶1,pH=7.0)溶液中,研究了FHBS作为检测探针对Hg2+的识别性能.结果表明,该探针对Hg2+具有高选择性和灵敏性,其它阴、阳离子的存在不干扰其对汞离子的测定.另外,Hg2+的加入使探针溶液从无色变为亮黄色,荧光从无色变为亮绿色,因此该探针为Hg2+的比色/荧光双模式探针,并可用于细胞的荧光成像.  相似文献   

9.
采用与文献不同的路线合成了4,4′-二(p-甲基苯基)-2,2′-二联吡啶,与文献结果相比,总收率由4.0%提高至15.3%.该化合物和4,4′-二羧基-2,2′-二联吡啶组成混合配体与金属钌配位,合成了两亲性、混配型配合物cis-N,N-4,4′-二(p-甲基)苯基-2,2′-二联吡啶-N,N-4,4′-二羧基-2,2′-二联吡啶-N,N-二异硫氰钌配合物,并用IR,UV-Vis,NMR和Maldi-TOF等手段进行表征.将该两亲性混配钌配合物首次用于对Hg2+的识别中,发现此配合物对Hg2+表现出灵敏的选择性“肉眼”识别:在DMF/乙醇溶液(体积比1∶9)中加入Hg2+后,MLCT态吸收由530nm蓝移到485nm.该配合物与Hg2+以1∶1(摩尔比)结合,检测限可低至0.5×10-6mol/L.  相似文献   

10.
基于罗丹明染料和菁染料衍生物,设计合成了一种新型近红外比率Cu2+荧光探针(RCy7).通过核磁共振和质谱对其结构进行了表征.详细研究了该荧光探针对Cu2+的光学识别性能.在体积比为1∶1的乙腈/Tris-HCl(20 mmol/L,pH=7.2)缓冲溶液中,探针RCy7显蓝色且在722 nm波长处有较强的荧光发射峰,...  相似文献   

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Single crystals of Ca2+, Sr2+, Ba2+, and Pb2+ beta″ alumina were prepared from sodium beta″ alumina by ion exchange. The ionic conductivities of Ca2+, Sr2+, and Ba2+ beta″ alumina are comparable, about 3 × 10?2 (ohm-cm)?1 at 300°C. Surprisingly, Pb2+ beta″ alumina is much more conductive, 1.5 × 10?1 (ohm-cm)?1 at 300°C and 4.6 × 10?3 (ohm-cm)?1 at 40°C. Its conductivity approaches that of sodium beta″ alumina at temperatures below 25°C. The diffusion coefficient for Sr2+ in beta″ alumina at 600°C was estimated from radiotracer experiments. It is consistent with that expected from conductivity measurements.  相似文献   

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14.
High-resolution translational-energy spectroscopy (up to 0.1 eV) has been carried out on 8
V beams of NO? and NO2?. Several features in the spectrum of NO4 are assigned to the transitions within the triplet manifold of this ion. The observed transitions originate in several excited electronic states, indicating long lifetimes (> 10 μs) for the states involved. Two electronic transitions in NO2' have been observed at low energies which are attributed to excitations to the first two excited states of this ion.  相似文献   

15.
The solubility polytherms in the systems for which the cryoscopic data are lacking were measured. The structural models of the electrolyte solutions were discussed on the basis of the solubility polytherms.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 413–417.Original Russian Text Copyright © 2005 by Pestova, Myund, Khripun, Prigaro.  相似文献   

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Lifetimes of selected vibrational levels of the predissociated Ã2Σ+ and Ã2Π electronic states of N2O+ and COS+, re- spectively, have been measured. These values have been used in conjunction with previous data on fluorescence quantum yields to obtain predissociation rates for the various vibrational levels.  相似文献   

19.
The B3LYP/6-311++G (d,p) density functional approach was used to study the gas-phase metal affinities of Guanosine (ribonucleoside) for the Li+, Na+, K+, Mg2+, Ca2+, Zn2+, and Cu+ cations. In this study we determine coordination geometries, binding strength, absolute metal ion affinities, and free energies for the most stable products. We have also compared the results for Guanosine, with our previously reported results for 2′-Deoxyguanosine. Based on the results, it is obvious that MIA is strongly dependent on the charge-to-size ratio of the cation. Guanosine interacts more strongly with Zn2+ than do with Mg2+, Ca2+, and Cu+ and therefore stronger interactions lead to higher MIA. In both free molecules and their complexes, the Syn orientation of the base is stabilized by an intramolecular O5′–H···N3 hydrogen bond and the anti orientation of the base is stabilized by an intramolecular C–H···O hydrogen bond formed between the (C8-H8) and the O5′ atom of the sugar moiety. It is also interesting to mention that linear correlation between calculated MIA values and the atomic numbers (Z) of the metal ions of Li+, Na+, and K+ were found. Furthermore, the influences of metal cationization on the strength of the N-glycosidic bond, torsion angles, angle of pseudorotation (P), and intramolecular C–H···O and O–H···O hydrogen bonds have been studied. Natural bond orbital (NBO) analysis was performed to calculate the charge transfer and natural population analysis of the complexes. Quantum theory of atoms in molecules (QTAIM) was also applied to determine the nature of interactions.  相似文献   

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