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1.
SILAR法制备化学计量CuInS2薄膜   总被引:1,自引:0,他引:1  
在室温下,以不同cCu/cIn的CuCl2和InCl3混合溶液作为阳离子前驱体,Na2S水溶液为硫源,利用连续离子层吸附反应法(SILAR)在玻璃基底上制备了CuInS2薄膜。XRD结果表明,当cCu2+/cIn3+在1~1.5范围内均可形成具有黄铜矿结构的CuInS2薄膜。SEM观察到随cCu2+/cIn3+的升高,薄膜表面颗粒长大并出现团簇聚集。通过XPS测定薄膜表面的化学组成证明当cCu2+/cIn3+=1.25时,CuInS2薄膜接近其标准的化学计量组成。此时薄膜的吸收系数大于>104 cm-1,禁带宽度Eg为1.45 eV。  相似文献   

2.
以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P21/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比为6∶4的DMSO/H2O缓冲溶液(Tris-HCl,pH=7.0)中研究了探针CMP对Cu2+的选择性识别。研究结果表明,探针CMP与Cu2+以1∶2的比例配位,结合常数为1.52×105 L·mol-1,检出限为0.205 μmol·L-1。回收实验表明,探针分子CMP可应用于环境水样中Cu2+的检测。  相似文献   

3.
Cu2+与烟草多酚氧化酶相互作用研究   总被引:3,自引:0,他引:3       下载免费PDF全文
本文通过酶活性测定,荧光光谱和紫外光谱研究了外加Cu2+与烟草多酚氧化酶(简称PPO)的相互作用。结果表明,微量铜的加入能增加酶的活性,[Cu2+]/[PPO]为0.20左右时酶活性最大,[Cu2+]/[PPO]为0.91时,Cu2+开始表现出对PPO活性的抑制;Cu2+对PPO内源荧光的猝灭机制属于形成络合物所引起的静态猝灭,猝灭常数Ksv为8.0375×103L·mol-1;Cu2+的加入使PPO蛋白质分子构象发生变化,α-螺旋含量增加,多肽链及Trp和Tyr残基的芳杂环进一步向分子内收缩,疏水基团之间的疏水作用增强。  相似文献   

4.
用不同的预处理气氛制备了CeO2/γ-Al2O3载体以调节表面Ce的价态,并以Cu(CH3COO)2为前驱体制备了CuCeAl催化剂。XRD和H2-TPR的结果表明在还原气氛下处理的CeO2/γ-Al2O3载体具有更多的活性氧原子,因此相应的CuCeAl催化剂表面有更多分散态的Cu2+/Cu+物种。NO+CO反应的结果表明分散态的Cu2+/Cu+是NO转化的活性物质,而Cu0在低温下具有较好的N2选择性。因此,同时含有分散态Cu2+/Cu+和少量晶相Cu0的催化剂具有最好的催化性能。  相似文献   

5.
通过在不同pH值下的简易水热法合成不同Yb3+离子(nYb3+/nLu3+=5%~15%)和Er3+离子(nEr3+/nLu3+=1%~5%)掺杂浓度的LuF3∶Yb3+,Er3+微晶荧光粉。发现pH值对正交相LuF3∶Yb3+,Er3+的合成起着关键作用。在980 nm激发下,LuF3∶Yb3+,Er3+荧光体呈现出以523 nm(2H11/24I15/2)和539 nm(4S3/24I15/2)为中心的强绿光上转换(UC)发射以及以660 nm(4F9/24I15/2)为中心弱红光上转换发射。通过使用X射线衍射(XRD)和光致发光(PL)分析测定了最强发射强度的Er3+和Yb3+的最佳掺杂浓度。浓度依赖性研究表明,达到最强的绿光上转换发光时最佳掺杂浓度为10% Yb3+,2% Er3+。通过改变泵浦功率来研究LuF3∶Yb3+,Er3+荧光粉UC发光机制。通过980 nm二极管激光器在293~573 K的范围内研究了在523和539 nm处的2个绿光UC发射带的荧光强度比(FIR)的温度依赖性,发现在490 K得到最大灵敏度约为15.3×10-4 K-1。这表明LuF3∶Yb3+,Er3+荧光体可应用于具有高灵敏度的光学温度传感器。  相似文献   

6.
希土离子取代对Eu2+发光的影响   总被引:4,自引:0,他引:4  
研究了具有磁铅矿和β-Al2O3结构的多铝酸盐基质中希土离子取代对Eu2+发光的影响。结果表明希土离子取代对Eu2+的发射峰位置和强度产生了较大变化,特别在磁铅矿基质中,这种影响更为显著。通过离子取代规则,获得了新的组成并具有β-Al2O3结构和磁铅矿结构的荧光体。  相似文献   

7.
手性配体立体选择性萃取分离扁桃酸对映体   总被引:6,自引:0,他引:6  
Based on chiral ligand exchange, the distribution behavior of mandelic acid enantiomers in the two-phase system containing copper ion(Ⅱ)(Cu2+) and N-n-dedecane-L-hydroxyproline (L), was studied. At different pH, the partition of Cu2+ in the two-phase system containing N-n-dedecane-L-hydroxyproline, was investigated. The formation constant of binary cpmplex(Li2Cu) was obtained by regression. The influence of pH, concentrations of Cu2+ and chiral ligand, and solvents on partition coefficients(K) and separation factor(α), was discussed. The experimental results show that Li forms more stable ternary complex with D-mandelic acid than with L- mandelic acid. There is a large influence of pH on K and α. At low pH values (<3.5), formation of binary complexes is thermodynamically unfavourable. K and α are best when pH values are above 3.5 and the molar ratio of chiral ligand to Cu2+ is 2∶1. At the same time, solvents influence K and α very much.  相似文献   

8.
稀土硝酸盐和2,5-噻吩二甲酸与菲咯啉在水热反应条件下合成了3个新的配合物,[Ln(2,5-tdc)1.5(phen)(H2O)]n(Ln=Gd(1),Tb(2),Dy(3);2,5-tdc=2,5-噻吩二甲酸根,phen=菲咯啉)。通过X射线单晶衍射确定了它们的晶体结构。配合物1~3为同构的2D网络结构。配合物1在340 nm激发下出现最大发射中心位于366和387 nm的宽峰,可归属于配体的π*-π跃迁发射。配合物2在365 nm紫外灯照射下发绿光,其荧光发射光谱中出现了4个尖峰,位于491、545、588和620 nm处,对应于Tb3+5D47FJJ=6~3)跃迁。配合物2的荧光寿命显示为单指数衰减,其值为(0.123±0.005)ms。配合物3的发射光谱中出现了2个尖峰,位于482和575 nm处,分别对应于Dy3+4F5/26H15/24F5/26H13/2跃迁。另外,研究了配合物2的荧光传感能力,该配合物可作为荧光探针检测水溶液中的Cu2+离子。  相似文献   

9.
采用传统的高温固相法合成了Cd3Al2Ge3O12: Mn2+长余辉发光材料, 利用X射线粉末衍射仪、荧光光谱仪、热释光谱计量仪等手段对粉末样品进行了表征。研究了以Zr4+离子作为辅助激活剂离子, 对发光材料Cd3Al2Ge3O12: Mn2+余辉性能的影响。分析结果表明, 样品位于500~700 nm的黄光宽带发射峰源于Mn2+4T1(4G)→6A1(6S)跃迁发射结果。并且观察到了由Cd3Al2Ge3O12基质向激活剂离子Mn2+的能量传递。共掺杂Zr4+离子后样品发射峰位没有明显变化, 但是余辉亮度衰减曲线表明适量的Zr4+离子掺杂可延长Cd3Al2Ge3O12: Mn2+的余辉时间。通过对热释光谱的分析, 解释了双掺杂荧光粉余辉性能增强的原因, Zr4+的掺杂在材料中引入了深度更为合适的缺陷陷阱, 可有效存储光能, 增强余辉的时间和强度。  相似文献   

10.
杨扬  丛妍  肖宇  付悦  夏胜强  董斌 《无机化学学报》2015,31(8):1529-1533
采用传统的高温固相法合成了Cd3Al2Ge3O12:Mn2+长余辉发光材料,利用X射线粉末衍射仪、荧光光谱仪、热释光谱计量仪等手段对粉末样品进行了表征。研究了以Zr4+离子作为辅助激活剂离子,对发光材料Cd3Al2Ge3O12:Mn2+余辉性能的影响。分析结果表明,样品位于500~700 nm的黄光宽带发射峰源于Mn2+4T1(4G)→6A1(6S)跃迁发射结果。并且观察到了由Cd3Al2Ge3O12基质向激活剂离子Mn2+的能量传递。共掺杂Zr4+离子后样品发射峰位没有明显变化,但是余辉亮度衰减曲线表明适量的Zr4+离子掺杂可延长Cd3Al2Ge3O12:Mn2+的余辉时间。通过对热释光谱的分析,解释了双掺杂荧光粉余辉性能增强的原因,Zr4+的掺杂在材料中引入了深度更为合适的缺陷陷阱,可有效存储光能,增强余辉的时间和强度。  相似文献   

11.
杜会枝  杨频 《中国化学》2006,24(3):345-349
Using the whole cell patch clamp technique, the effect of Cu^2+on transient outward K^+current (/to) and delayed rectifier K^+ current (Idr) was studied in acutely isolated rat hippocampal neurons.Ito and Idr were increased when the concentration of Cu^2+ was lower than 2 × 10^-5 and 10^-5 tool/L, respectively, and increased ratio was decreased with increasing Cu^2+concentration in the bath solutions. When the concentration continued to increase to 5× 10^-5 and 2 × 10^- 5 mol/L, the currents were hardly changed, while the concentration was more than 10^-4 and 5 × 10^-5 mol/L, the currents were inhibited remarkably. Cu^2+ (10^-5 mol/L) did not affect the activation and inactivation process of Ito. The activation curve of Idr was shifted toward positive potential, but 10^-5 mol/L Cu^2+did not affect slope factor. According to these results, it was considered that Cu^2+at low concentration in the bath solution could promote Ito and Idr while at high concentration could inhibit them, and change of amplitude was different with different membrane voltage. Conclusion was drawn: Cu^2+may be involved in the pathophysiologic mechanism of diseases with neuropathological components.  相似文献   

12.
Rigid N‐(substituted)‐2‐aza‐[3]‐ferrocenophanes L1 and L2 were easily synthesized from 1,1 ‐dicarboxyaldehydeferrocene and the corresponding amines. Ligands L1 and L2 were characterized by 1H NMR, 13C NMR and single‐crystal X‐ray crystallography. The coordination abilities of L1 and L2 with metal ions such as Cu2+, Mg2+, Ni2+, Zn2+, Pb2+ and Cd2+ were evaluated by cyclic voltammetry. The electrochemical shift (ΔE1/2) of 125 mV was observed in the presence of Cu2+ ion, while no significant shift of the Fc/Fc + couple was observed when Mg2+, Ni2+, Zn2+, Pb2+, Cd2+ metal ions were added to the solution of L1 in the mixture of MeOH and H2O. Moreover, the extent of the anodic shift of redox potentials was approximately equal to that induced by Cu2+ alone when a mixture of Cu2+, Mg2+, Ni2+, Zn2+, Pb2+ and Cd2+ was added to a solution of L1. Ligand L1 was proved to selectively sense Cu2+ in the presence of large, excessive first‐row transition and late‐transition metal cations. The coordination model was proposed from the results of controlled experiments and quantum calculations. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

13.
Summary Two fluorescence techniques to study metal-humic interactions are presented. In the first technique, Lanthanide Ion Probe Spectroscopy (LIPS), the humic samples are titrated by Eu3+ ions. The ratio of the intensities of two emission lines of Eu3+, R=I592/I616, is used to estimate the amount of bound and free species of the probe ions. The titration plot is presented as R versus the logarithm of total added Eu3+. In the second technique, fluorescence quenching of the humic material by Cu2+ is used to produce titration curves of intensity versus the logarithm of total added Cu2+. The two techniques are used in conjunction with a model that treats the various ligands in humic substances as continuous distributions of binding sites in which individual ligand concentrations are normally distributed with respect to the individual stability constants for metal binding. The model includes the effects of pH, ionic strength, and competing metal ions. The parameters of the model are estimated by fitting the spectral titration data to the calculated titration plot. Some simulation and experimental data are presented and discussed.  相似文献   

14.
A new diarylethene compound with a triazole-linked rhodamine 6G unit attached to the imino group (1O) was designed and synthesized. According to the test results, the solution color and fluorescence color of diarylethene can be modulated by lights and metal ions. The solution color could change from colorless to light purple when irradiated with UV light. When Cu2+ was added to the diarylethene solution, the color of diarylethene solution became blue, the fluorescence color turned from dark to bright yellow. Although the solution color did not change by adding Fe3+, its fluorescence color varied from dark to yellow. Moreover, it was found that the complex ratio of the diarylethene to Cu2+ was 1:1 and the binding stoichiometry of the diarylethene to Fe3+ was also 1:1 based on the data of NMR, MS, and other experiments. Based on these findings, photochromic figure of the diarylethene with UV/Vis light, Cu2+ and Fe3+ was constructed. Furthermore, the logic circuit was designed by input signals (ultraviolet stimulus, visible light stimulus, Cu2+ (or Fe3+) and EDTA) and an output signal (fluorescent intensity at 566?nm (or 575?nm)).  相似文献   

15.
罗丹明6G缔合微粒荧光猝灭法测定痕量碘酸根   总被引:2,自引:2,他引:0  
研究发现在0.01mol/LHCl-8.0×10-4mol/LKI介质中,罗丹明6G(RhG)在550nm处有1个荧光峰.当有IO-3,I-3与RhG形成缔合微粒,550nm处荧光峰猝灭,在320、400、6103存在时,IO-3与过量的I-反应生成I-nm处有3个共振散射峰,在470nm处有1个同步散射峰.碘酸根浓度在2.0~100×10-7mol/L范围内与荧光猝灭强度成线性关系.据此建立了一个测定食盐中IO-3的荧光猝灭分析法.光谱研究结果表明,(RhG-I3)n缔合微粒和界面的形成是导致体系荧光猝灭的根本原因.  相似文献   

16.
A new Schiff base fluorescence probe, 3-Allylsalicylaldehyde salicylhydrazone (L), for Mg2+ was designed and synthesized. The fluorescence of the sensor L was enhanced remarkably by Mg2+ with 2:1 binding ratio, and the binding constant was determined to be 1.02 × 107 M?1. Probe L had high sensitivity for Mg2+ in a solution of DMF/water (4:1, v/v, pH 7.5), and the detection limit was 4.88 × 10?8 mol/L. Common coexistent metal ions, such as K+, Na+, Ag+, Ca2+, Zn2+, Ba2+, Bi2+, Cu2+, Ni2+, Hg2+, Fe3+ , and Al3+, showed little or no interference on the detection of Mg2+ in solution. The fluorescence probe L, which was successfully used for the determination of trace Mg(II) in real samples, was shown to be promising for liquid-phase extraction coupled with fluorescence spectra.  相似文献   

17.
A new perylene diimide (PDI) ligand (1) functionalized with a dipicolylethylenediamine (DPEN) moiety was synthesized and first used as a colorimetric and fluorometric dual-channel sensor to specifically detect the presence of Cu2+ over a wide range of other cations. The solution of 1 (10 μmol/L) upon addition of Cu2+ displayed distinguishing pink color compared with other cations including K+, Ni2+, Ca2+, Mn2+, Na+, Sr2+, Zn2+, Co2+, Cd2+, Mg2+, Cr3+, Ag+, and Ba2+, indicating the sensitivity and selectivity of 1 to Cu2+. Thus, the advantage of this assay is that naked-eye detection of Cu2+ becomes possible. Moreover, among these metal ions investigated, only Cu2+ quenched more than half fluorescent intensity of 1. The ESI-TOF spectrum of a mixture of 1 and CuCl2 in combination of the fluorescence titration spectra of 1 (10 μmol/L) upon addition of various amounts of Cu2+ revealed the formation of a 2:1 metal-ligand complex through the metal coordination interaction. Supported by the National Natural Science Foundation of China (Grant Nos. 20872101 & 20772086)  相似文献   

18.
The dioxygen activation of a series of CuICuICuI complexes based on the ligands ( L ) 3,3′‐(1,4‐diazepane‐ 1,4‐diyl)bis(1‐{[2‐(dimethylamino)ethyl](methyl)amino}propan‐2‐ol) ( 7‐Me ) or 3,3′‐(1,4‐diazepane‐1,4‐diyl)bis(1‐{[2‐(diethylamino)ethyl](ethyl)amino}propan‐2‐ol) ( 7‐Et ) forms an intermediate capable of mediating facile O‐atom transfer to simple organic substrates at room temperature. To elucidate the dioxygen chemistry, we have examined the reactions of 7‐Me , 7‐Et , and 3,3′‐(1,4‐diazepane‐1,4‐diyl)bis[1‐(4‐methylpiperazin‐1‐yl)propan‐2‐ol] ( 7‐N‐Meppz ) with dioxygen at ?80, ?55, and ?35 °C in propionitrile (EtCN) by UV‐visible, 77 K EPR, and X‐ray absorption spectroscopy, and 7‐N‐Meppz and 7‐Me with dioxygen at room temperature in acetonitrile (MeCN) by diode array spectrophotometry. At both ?80 and ?55 °C, the mixing of the starting [CuICuICuI( L )]1+ complex ( 1 ) with O2‐saturated propionitrile (EtCN) led to a bright green solution consisting of two paramagnetic species: the green dioxygen adduct [CuIICuII(μ‐η22‐peroxo)CuII( L )]2+ ( 2 ) and the blue [CuIICuII(μ‐O)CuII( L )]2+ species ( 3 ). These observations are consistent with the initial formation of [CuIICuII(μ‐O)2CuIII( L )]1+ ( 4 ), followed by rapid abortion of this highly reactive species by intercluster electron transfer from a second molecule of complex 1 to give the blue species 3 and subsequent oxygenation of the partially oxidized [CuIICuICuI( L )]2+ ( 5 ) to form the green dioxygen adduct 2 . Assignment of 2 to [CuIICuII(μ‐η22‐peroxo)CuII( L )]2+ is consistent with its reactivity with water to give H2O2 and the blue species 3 , as well as its propensity to be photoreduced in the X‐ray beam during X‐ray absorption experiments at room temperature. In light of these observations, the development of an oxidation catalyst based on the tricopper system requires consideration of the following design criteria: 1) rapid dioxygen chemistry; 2) facile O‐atom transfer from the activated cluster to substrate; and 3) a suitable reductant to rapidly regenerate complex 1 to accomplish efficient catalytic turnover.  相似文献   

19.
New imidazole‐functionalized disubstituted polyacetylene was synthesized by utilizing the postfunctional strategy. In addition, its ability to sense copper ions and α‐amino acids by fluorescence quenching has been studied. The quenching of the fluorescence of the imidazole‐functionalized disubstituted polyacetylene was observed at a very low level of Cu2+ (7.0 × 10−7 mol · L−1). The fluorescent intensity decreased rapidly upon the increase of the concentration of the added solution of Cu2+. It was expected that the addition of α‐amino acids to the solution of the polyacetylene/Cu2+ complex could turn on the fluorescence of the polyacetylene, if α‐amino acids could remove the copper ions from the complex. Glycine, was used for testing: upon the addition of glycine the quenched fluorescence of P1 turned on immediately. The detection limit was as low as 6.0 × 10−5 mol · L−1.

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20.
A novel fluorescent probe CN3, containing 1,8-naphthalimide and picolinate units, was synthesized, and its structure was characterized by 1H nuclear magnetic resonance spectroscopy (H NMR), 13C nuclear magnetic resonance spectroscopy (C NMR), and mass spectroscopy techniques. The detection property of CN3 toward copper ions (Cu2+) has been investigated in ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) solution by UV–Vis absorption and fluorescence emission spectra. The results showed that CN3 had a highly selective and sensitive fluorescence quenching response to Cu2+, which was attributed to the generation of weak fluorescent N-ethyl-4-hydroxyphenyl-1,8- naphthalimide (compound 2) in polar ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) via selective hydrolysis reaction. The detection of CN3 for Cu2+ was not influenced in the presence of other competing metal ions, and the limit of detection was as low as 50.0 nM. Therefore, the color of CN3 changed from colorless to yellowish when the Cu2+ was added. Furthermore, the fluorescent probe CN3 was utilized to detect Cu2+ in real water samples with fine performance.  相似文献   

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