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1.
由N-乙基咔唑-3-甲醛(NECD)与乙二胺(EDA)合成N-乙基咔唑席夫碱化合物EDA-NECD,用IR、1 H NMR等手段表征其结构;研究各种金属离子对其荧光性能的影响,结果表明Cu2+能显著地猝灭其荧光,而余者则几无影响;其紫外吸收峰值随着Cu2+浓度的增加而增加,表明二者存在着化学反应。EDA-NECD有望作为重金属离子Cu2+的荧光探针。  相似文献   

2.
A new designed colorimetric and fluorescent dye chemosensor was synthesized, characterized and computationally calculated using MO theory calculation, which was based on donor-pi-acceptor electron charge transfer system. This particularly designed dye chemosensor displayed the selective Ni2+ ion chemo-sensing effects in optical properties with absorption and fluorescence emission. This dye chemosensor represented clear absorption spectra changes with Ni2+ ion and the dramatic fluorescence quenching effect with Ni2+ ion was determined. However it showed no significant optical spectra changes upon the addition of other metal ions such as Cd2+, Na2+, Mg2+, Pb2+, Fe2+, Fe3+, Ca2+, Cu2+, Hg2+, except Zn2+.  相似文献   

3.
韩巧荣  江玉亮  王炳祥 《功能材料》2012,43(14):1822-1824
合成了荧光性能良好的中氮茚化合物5,用IR、1 H NMR等手段表征其结构;研究各种金属离子对其荧光性能的影响,结果表明Cu2+能显著地猝灭其荧光,而余者则几无影响;其紫外吸收峰值随着Cu2+浓度的增加而增加,表明二者存在着化学反应。此化合物有望作为重金属离子Cu2+的荧光探针。  相似文献   

4.
两种新型咔唑类双光子光聚合引发剂的合成与光学性质   总被引:4,自引:0,他引:4  
报道了两种新型的咔唑类双光子光聚合引发剂,3,6-双[2-(4-吡啶基)乙烯基]-9-苯基咔唑(1) 和 3,6-双[2-(2-吡啶基)乙烯基]-9-苯基咔唑(2),它们是通过钯催化的Heck偶连反应合成得到,并用元素分析,红外光谱,核磁共振氢谱和电喷雾电离质谱等对它们进行了全面的表征.这两个A-π-D-π-A结构的咔唑衍生物具有很好的单光子和双光子荧光行为,我们也详细研究了它们的溶剂效应和作为双光子引发剂用于微结构的制备,并讨论了它们的引发聚合的机理.  相似文献   

5.
李保卫  张志云  邹祺 《材料导报》2017,31(Z2):67-71
合成了一种茚修饰的蒽类衍生物(INAN)——9,10-二[4-(1,1-二甲基-3-苯基-1H-茚)苯基]蒽,经核磁共振氢谱、碳谱以及高分辨质谱等手段表征了其结构。应用紫外-可见吸收光谱、荧光光谱、循环伏安法和热重分析研究了其光物理、电化学和热稳定性能,计算了其HOMO、LUMO能级和电化学能隙。并将其与工业应用的9,10-二(4-(2,2-二苯乙烯基)苯)蒽进行性能比对,发现该材料的荧光发生蓝移,同时在热稳定性和发光量子产率上均有改善。该类化合物可作为高效的蓝光荧光材料,应用于有机电致发光材料及生物显像等领域。  相似文献   

6.
We report blue fluorescent organic light-emitting devices (OLED) by solution process utilizing a blue emitting small molecule, 2,7-bis[(9-ethyl-9H-carbazol-3-yl)ethenyl]-9,9-bis(4-n-octyloxyphenyl)-9H-fluorene (CB), which has good solubility in common organic solvent. The peak positions of absorption and emission spectra of a new fluorene-based molecule in tetrahydrofuran solution were observed at 399 and 439 nm, respectively. We achieved a maximum luminous efficiency of approximately 3 cd/A with CIE color coordinates of (0.15, 0.15) in our device.  相似文献   

7.
A microcantilever array sensor with cantilevers differentially functionalized with self-assembled monolayers (SAMs) of thiolated ligands is prepared by simultaneous capillary coating. This array is described for the detection of metal ions including Li+, Cs+, Cu2+, Co2+, Fe3+, and Al3+. Binding of the charged metal cations to the surface of the microcantilever sensors produces surface stress that causes bending of the cantilevers that is detected as tip deflection using an array of vertical cavity surface emitting lasers and a position-sensitive detector. Optimization studies of the nanostructured dealloyed surface were performed for SAMs based on their response to Cu2+ cations. Sensor performance experiments demonstrate good sensitivity toward metal ions, with limits of detection as low as 10(-8) molar. A multiplex capillary coating method for cantilever array creation is demonstrated and validated based on surface-enhanced Raman spectra obtained from adjacent cantilevers that were functionalized with different thiolated SAMs. The cantilever array coated with a range of thiolated ligands was exposed to the group of metal ions. The response characteristics of each metal ion show substantial diversity, varying not only in response magnitude, but response kinetics. A pattern recognition algorithm based on a combination of independent component analysis and support vector machines was able to validate that the sensor array response profiles produced enough information content that metal ions could be reliably classified with probabilities as high as 89%.  相似文献   

8.
The voltage-driven transfer of alkali and alkaline-earth metal ions across the polarized 1,2-dichloroethane (DCE)/water interface has been measured fluorometrically by using two fluorescent ionophores, coumarin 153-linked monoaza-15-crown-5 (C153-crown(O(4))) and two-coumarin 153-linked diaza-18-crown-6 ((C153)(2)-K(22)). The 1:1 complex formation prevails for both monovalent and divalent ion transfer, when the concentration of C153-crown(O(4)) in DCE is at the micromolar level. In the Mg(2+) ion transfer, the formation of the 1:2 (metal-ligand) complex becomes significant at the millimolar level of C153-crown(O(4)). C153-crown(O(4)) seems to adsorb at the interface. The complexation of Ba(2+) with (C153)(2)-K(22) is significantly slower than the complexation with C153-crown(O(4)).  相似文献   

9.
Efficient reversible phototransformation of a new diarylethene-fluorene derivative, 1,2-bis(5-(9,9-didecyl-7-nitro-9H-fluoren-2-yl)-2-methylthiophen-3-yl)cyclopent-1-ene (1), was demonstrated in organic media under low-intensity laser excitation. Linear photophysical characterization of 1 was performed at room temperature in solvents of different polarity and viscosity. Significantly, close to unity quantum yield for the cyclization reaction of 1 was shown in nonpolar solutions. The lifetimes of the excited states of the open (OF) and closed (CF) forms of 1 were measured by a femtosecond transient absorption technique, and corresponding values of ~0.7 and ~0.9 ps were shown in dichloromethane (DCM), respectively. Degenerate two-photon absorption (2PA) spectra of the OF and CF of 1 were obtained over a broad spectral range by the open aperture Z-scan method under 1 kHz femtosecond excitation. The values of 2PA cross sections of the OF in DCM (~50-70 GM) were found to increase up to 1 order of magnitude (~600 GM) after cyclization to the CF. The nature of cyclization and cylcoreversion processes were investigated by quantum chemistry with employment of DFT-based methods implemented in the Gaussian'09 program. The potential of 1 for application in optical data storage was shown using poly(methyl methacrylate)-doped films and two-photon fluorescence microscopy readout.  相似文献   

10.
Funalia trogii biomass was immobilized in Ca-alginate gel beads. The live and heat inactivated immobilized forms were used for the biosorption of Hg2+, Cd2+ and Zn2+ ions by using plain Ca-alginate gel beads as a control system. The effect of pH was investigated and the maximum adsorption of metal ions on the Ca-alginate and both live and inactivated immobilized fungal preparations were observed at pH 6.0. The temperature change between 15 and 45 degrees C did not affect the biosorption capacity. The biosorption of Hg2+, Cd2+ and Zn2+ ions on the Ca-alginate beads and on both immobilized forms was studied in aqueous solutions in the concentration range of 30-600 mg/L. The metal biosorption capacities of the heat inactivated immobilized F. trogii for Hg2+, Cd2+ and Zn2+ were 403.2, 191.6, and 54.0 mg/g, respectively, while Hg2+, Cd2+ and Zn2+ biosorption capacities of the immobilized live form were 333.0, 164.8 and 42.1 mg/g, respectively. The same affinity order on a molar basis was observed for single or multi-metal ions (Hg2+ > Cd2+ > Zn2+). The Langmuir and the Freundlich type models were found to exhibit good fit to the experimental data. The experimental data were analyzed using the first-order (Langergren equations) and the second order (Ritchie equations). The experimental biosorption capacity with time is found to be best fit the second-order equations. The alginate-fungus system could be regenerated by washing with a solution of hydrochloride acid (10 mM). The percent desorption achieved was as high as 97. The biosorbents were reused in five biosorption-desorption cycles without significant loss of their initial biosorption capacity.  相似文献   

11.
The H3+ ion and its deuterated isotopologues H2D+, D2H+ and D3+ play an important role in astrophysical and laboratory plasmas. The main challenge for understanding these ions and their interaction at low temperatures are state-specific experiments. This requires manipulation and a simple but efficient in situ characterization of their low-lying rotational states. In this contribution we report measurements of near infrared (NIR) absorption spectra. Required high sensitivity is achieved by combining liquid nitrogen cooled plasma with the technique of NIR cavity ringdown absorption spectroscopy. The measured transition frequencies are then used for exciting cold ions stored in a low-temperature 22-pole radiofrequency ion trap. Absorption of a photon by the stored ion is detected by using the laser-induced reactions technique. As a monitor reaction, the endothermic proton (or deuteron) transfer to Ar is used in our studies. Since the formed ArH+ (or ArD+) ions are detected with near unit efficiency, the stored ions can be characterized very efficiently, even if there are just a few of them.  相似文献   

12.
The YbS /Er3 doped TeO2-WO3-ZnO glasses were prepared. The absorption spectra, emission spectra and fluorescence lifetime of Era at 1.5μm, excited by 970 nm were measured. The influence of Er2Oa, Yb2Oa and Ohcontents on emission properties of Era at 1.5 μm was investigated. The optimum doping concentrations for Era and Yba is around 3.34× 1020 ions/cma and 6.63×1020 ions/cma, respectively. The peak emission cross section is 0.83~0.87 pm2. With the increasing concentration of Yba , the FWHM of Era emission at 1.5 μm in the glass increases from 77 nm to 83 nm. The results show that Yba /Era doped meO2-Woa-ZnO glasses are promising candidate for Era -doped broadband optical amplifier.  相似文献   

13.
Broadband terahertz time-domain spectroscopy (THz-TDS) has been used to measure the far-infrared (FIR) vibrational spectra of several commonly used pure explosives, including 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), 1,3-dinitrato-2,2-bis(nitratomethyl)propane (PETN), and two types of plastic explosive, SEMTEX and SX2. A number of distinct absorption peaks, originating from FIR-active vibrational modes of these polycrystalline energetic materials, were observed in the frequency range 0.3-7.5 THz (10-250 cm(-1)). In addition, the temperature-dependent FIR vibrational spectra of PETN were measured between 4 K and 296 K with several well-resolved absorption peaks observed across this temperature range. We find that as the temperature is reduced, the observed absorption peaks resolve into narrower features and shift towards higher frequencies. The temperature dependence of the spectra is explained in terms of the anharmonicity of the vibrational potentials of crystalline compounds, and an empirical fit is given to describe the peak shift with temperature.  相似文献   

14.
以丁二酮、液溴和硫脲为原料合成了2,2-二氨基-4,4-联噻唑(DABT);将DABT与对氨基苯甲酸和多聚甲醛共聚制得对氨基苯甲酸缩聚DABT聚合物,然后与铁、镍、铜的硫酸盐配合得到金属配合物。表征了产物结构,测试了产物的热性能、电导率、磁性能和荧光特性。结果表明,对氨基苯甲酸缩聚DABT聚合物的电导率优于配合有金属离子的聚合物,其值为3.12×10-6S/cm,处于半导体范围;配合Fe2+的聚合物具有一定的磁性能,表明配合Fe2+聚合物是一种有机软铁磁体;而配合Cu2+的聚合物能激发产生荧光,具有发射紫外-蓝光特性,可作为新型有机光功能材料。  相似文献   

15.
PAAS高吸水树脂对重金属离子盐溶液的吸液及吸附性能   总被引:1,自引:1,他引:1  
用聚丙烯酸高吸水树脂(PAAS)研究了单一和混合重金属离子硝酸盐溶液中的吸液和吸附性能.在Pb2 、Ni2 、Cd2 、Zn2 、Mn2 和Cu2 的一、二元溶液中,PAAS的吸液倍率随时间延长而增加,约50min达吸液平衡,一元金属离子溶液中平衡吸液倍率为160~190g/g,而对Cr3 溶液,最大为120g/g;二元金属离子混合溶液中平衡吸液倍率都在150~180g/g之间,有Cr3 存在时平衡吸液倍率最小.对上述单一金属离子的吸附量随时间延长而增加,约180min达吸附平衡,平衡吸附量顺序为:Pb2 >Cd2 >Ni2 >Cu2 >Zn2 >Mn2 >Cr3 .对二元混合金属离子溶液,吸附量随时间增加而增加,30min后逐渐变慢,约70min后达吸附平衡.  相似文献   

16.
掺Er~(3+)重金属氧氟锗酸盐玻璃光谱性质研究   总被引:1,自引:0,他引:1  
研究了重金属氧氟锗酸盐玻璃中Er3+离子的吸收光谱、有效吸收和发射线宽、荧光光谱、荧光半高宽、荧光寿命、带宽特性和增益性能.应用Judd-Ofelt理论计算了Er3+离子的强度参数Ωt(t=2,4,6),应用McCumber计算了能级4I13/2→4I15/2跃迁的吸收和受激发射截面.结果显示,随PbF2含量增加,Er3+离子的强度参数Ω6,吸收线宽、发射线宽、荧光半高宽、荧光寿命、带宽特性和增益性能都增加.表明掺Er3+重金属氧氟锗酸盐玻璃可作为宽带光纤放大器潜在的基质材料.  相似文献   

17.
Alpha-alumina is a useful thermoluminescence (TL) dosemeter. The knowledge of its behaviour under irradiation is thus of primary importance. The purpose of this paper is to characterise the radiation damage produced by swift krypton ions using various experimental methods, namely TL, optical absorption, fluorescence and electron paramagnetic resonance (EPR). After ion irradiation, the TL intensity is shown to decrease, whereas the optical absorption rises in the whole studied wavelength range. These two phenomena seem to be related to one another. Furthermore, optical absorption measurements highlight the appearance of new absorption bands probably owing to oxygen vacancies. Induced defects are also observed in the EPR spectra of irradiated pellets. They are likely related to electronic holes trapped on oxygen ions. The concentration of these defects increases with ion fluence and fluorescence measurements indicate that some pre-existing defects such as F2(2+) centres follow the same trend up to approximately 4.1 x 10(13) ions cm(-2).  相似文献   

18.
A novel ammonium ionophore, which exhibits superior NH4+ selectivity compared with that of the natural antibiotic nonactin, was successfully designed and synthesized based on a 19-membered crown compound (TD19C6) having three decalino subunits in the macrocyclic system. This bulky decalino subunit is effective for (1) increasing the structural rigidity of the cyclic compound, (2) introducing the "block-wall effect", which prevents forming a complex with a large ion, and (3) increasing the lipophilicity of the ionophore molecule. In the ammonium ionophore design, the first factor contributes to increasing the NH4+ selectivity relative to smaller ions such as Li+, Na+, or even the closest size, K+, and the second factor increases the NH4+ selectivity over larger ions such as Rb+ and Cs+. The X-ray structural analysis proved that TD19C6 forms a size-fit complexwith NH4+ in its crown ring cavity. As an application of this ionophore, an ion sensor (ion-selective electrode) was prepared, which exhibited NH4+ to K+ and Na+ selectivity of 10 and 3,000 times, respectively. This electrode showed a better performance compared to the electrode based on nonactin, which is the only ammonium ionophore presently used in practical applications.  相似文献   

19.
An azo-phenol based receptor 2 viz., 1-(6-nitrobenzothiazole-2-ylazo)naphthalene-2-ol has been designed, synthesized and characterized. The sensing behavior of receptor for different metal ions viz. Na+, K+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+, Hg2+, Ag+ and Cd2+ has been studied in aqueous acetonitrile solution and was found specific for both the Hg2+ and Cu2+ transition metal ions. The chemosensor upon interaction with Hg2+ and Cu2+ ions shows well defined naked-eye visible color change from a yellow-green to pink and blue respectively, with a significant red-shift in absorption spectra. The estimated association constant and, enhancement and quenching in fluorescence emission spectra respectively, reveals the affinity of chemosensor for Hg2+ and Cu2+ ions. The FT-IR spectral analysis have suggested the probability of complexation, in the reaction medium, between metal ions and 2, through naphthol OH, azo N and thiazole N as a potential coordination sites.  相似文献   

20.
Electrospray ionization (ESI)/quadrupole ion trap mass spectrometry is used to evaluate the heavy metal binding selectivities of five caged crown ethers and two polyether reference compounds in methanol solution. The binding preferences for Hg2+, Pb2+, Cd2+, and Cu2+ were analyzed by comparison of ESI mass spectral intensities with the aim of developing this method for the rapid screening of binding selectivities of new synthetic ligands. The cage compounds preferentially bind Hg2+, except for the cage cryptand derivative, which favors Pb2+. The preference for Hg2+ stems from the favorable positioning of the nitrogen or sulfur atoms for linear coordination of Hg2+, whereas the cryptand derivative favors Pb2+ because of its larger cavity size. The counterions of the metal salts influence the type of complexes observed in the ESI mass spectra because the strengths of the metal-anion bonds affect retention of the anion in the complexes.  相似文献   

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