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1.
Abstract

We report the synthesis and characterization of multifunctional polysilane copolymers containing chiral and azobenzene chromophore as a pendant group. Multifunctional polymers of poly(methylphenylsilane) (PMPS) with (R)-N-(1-phenylethyl)methacrylamide (R-NPEMAM) and disperse red 1 methacrylate (DR1MA) were synthesized in a quartz tube using UV-technique. The molecular weights of such synthesized copolymers were found to be in the order of 103. The appearance of two glass transition temperatures in DSC indicated that the synthesized copolymers are block copolymers. The electronic absorbance of synthesized polymers was observed at 272?nm (π-π* transition of aromatic ring), 330?nm (σ-σ* transition of Si-Si chain of PMPS) and 475?nm (n-π* with π-π* transition due to azobenzene chromophore of DR1MA unit). The chirality of the synthesized polymer was confirmed through circular dichroism observed at 261?nm. Induced chirality appeared at 330?nm and 470?nm due to the association of the Si-Si chain of PMPS and the presence of azobenzene chromophore of the DR1MA unit respectively. The photoluminescence (PL) properties of the synthesized copolymers (SCDRDM-1B, SCDRDM-2B, and SCDRDM-3B) were observed at 307?nm and 415?nm when excited at 275?nm. The λem was also observed at 415?nm when excited by 325?nm. The multi-emission spectra appeared at 500?nm, 550 and 590?nm are presumed to be due to exciton coupling between azobenzene chromophore of DR1MA, and Si-Si σ-conjugation in association with the aromatic ring of PMPS and chiral unit R-NPEMAM block.  相似文献   

2.
水溶液中丙酮的敏化室温磷光测定   总被引:1,自引:0,他引:1  
测定水溶液中微量丙酮,常用吸光光度法[1~3]和色谱法[4,5]等,这些方法固然灵敏度较高,但样品的预处理比较复杂,分析速度慢,线性范围窄.本文以丁二酮为能量受体,建立了水溶液中微量丙酮的敏化室温磷光测定法.方法简便快速,重现性好,灵敏度亦高.  相似文献   

3.
多环芳烃芴、苊的无保护流体室温磷光性质研究   总被引:3,自引:0,他引:3  
我们[1,2 ]曾报道丹磺酰氯及其衍生物在无保护性介质亦无有机溶剂存在的水溶液中能诱导出强而稳定的室温磷光 (RTP) ,并命名为NP RTP[37].此后 ,Carretero等[810 ]亦发现了萘唑啉、萘氧乙酸和苊溶液在无任何有序介质时的RTP发射现象 .在已有的研究中至少有两个问题需进一步探索 :其一 ,除苊外 ,已实现NP RTP发射的化合物都仅具双环结构 ,即萘系化合物 ,对于多环化合物是否有类似的发射特性和随环的增多是否会出现新的特性 ;其二 ,对于无水溶性取代基的多环芳烃 ,因其在水中的溶解度很小 ,所引入的有机溶剂的种类和…  相似文献   

4.
采用电化学聚合法制备了聚铬黑T膜修饰电极,应用扫描电镜、交流阻抗法和循环伏安法对修饰电极进行表征,以循环伏安法研究硫酸特布他林在修饰电极上的电化学行为,并以差示脉冲伏安法对其含量进行测定.该方法对硫酸特布他林有明显的电催化作用,在pH 7.0磷酸盐缓冲液中,氧化峰电流与硫酸特布他林浓度在1.2x10-7~2.0x10-6mol•L-1范围内呈良好的线性关系,检测限为1.5x10-8 mol•L-1,回收率在97.9%~104.6%之间,RSD在2.8 % (C=8x10-7mol•L-1,n=11).该方法简便灵敏,结果准确可靠,方法重复性好,可用于硫酸特布他林及其片剂的质量控制.  相似文献   

5.
钴-8-羟基喹啉-5-磺酸的荧光光度法的研究及应用   总被引:5,自引:0,他引:5  
以8-羟基喹啉-5-磺酸测定金属离子的荧光反应已有报道。我们研究了CoH2O2-8-羟基喹啉-5-磺酸(H2QS)体系,钴含量在3.7×10-7~2.5×10-5mol/L时,该方法能给出线性响应,试验了多种离子的干扰情况,拟定了植物样品中微量钴的测定方法,初步探讨了反应机理。  相似文献   

6.
Functional photoactive organic-inorganic block copolymers of poly(methylphenylsilane) (PMPS) and disperse red 1 methacrylate (DR1MA) were synthesized in a quartz tube using UV-technique. The synthesized block copolymers were characterized by FTIR, NMR, GPC and thermal analyses and studied for their optical and photoluminescence properties. The weight average and number average molecular weights of such a synthesized block copolymer are 2.47 × 103 and 2.27 × 103, respectively. The appearance of two glass transition temperatures indicated the synthesized polymers as block copolymers. The functional organic-inorganic block copolymers exhibited optical absorbance at 276 nm due to aromatic ring associated with both the blocks and at 325 nm due to σ-electron delocalization of Si-Si chain of PMPS block. Also, the optical absorbance appeared at 472 nm is due to combining the contribution of n-π* and first π-π* charge transfer electronic transition of the azobenzene chromophore of DR1MA unit. Two photoemissions were observed at 307 nm and 415 nm when such a polymer was excited at 275 nm. The photoluminescence was also observed at 415 nm when excited by 325 nm. The multi-emission spectra appeared between 510 nm to 580 nm are presumed to be due to exciton coupling between azobenzene chromophore of DR1MA and and Si-Si σ-conjugation of PMPS block. The synthesized copolymers are thermally stable up to 260°C. Such functional photoactive block copolymers may find novel optoelectronic application.  相似文献   

7.
制备了石墨烯-壳聚糖复合物修饰玻碳电极(GO/CS-GCE),考察了对乙酰氨基酚(APAP)在修饰电极上的电化学行为,发现石墨烯-壳聚糖复合物能较好改善玻碳电极对APAP的电化学性能,APAP在修饰电极上的电化学反应过程是受吸附控制的2电子,2质子反应过程;进一步研究发现在pH=9.16的碳酸钠-碳酸氢钠缓冲体系中,对...  相似文献   

8.
化学法沉积银岛膜上的表面增强拉曼散射(Ⅰ)   总被引:1,自引:0,他引:1  
用银镜反应在抛光的石英片上沉积银膜,经扫描电镜研究表明,控制反应条件可得到表面粒度为50~140nm的SERS活性银岛膜表面,将此活性表面直接插入含微量孔雀石绿水溶液中,测量吸附孔雀石绿分子的拉曼光谱,可获得105倍的拉曼增强,孔雀石绿浓度小到10-10mol/L时,仍能得到明确的光谱信息,给出了浓度与强度的关系,讨论了吸附作用对几个重要振动带的影响。  相似文献   

9.
合成了2种新的具有潜在应用价值的非线性光学(NLO)有机材料芳香查尔酮衍生物1-(呋喃-2-基)-3-(4-甲氧基苯基)丙烯酮(1)和1-(噻吩-2-基)-3-(4-甲氧基苯基)丙烯酮(2),并对其进行了NMR、IR和HR-MS结构表征。 采用4f相位相干成像技术测定了化合物1和2的三阶NLO性质并确定了相关参数:脉冲宽度4 nm,激光波长440 nm,化合物1:非线性吸收系数β=5.5×10-10 m/W,非线性折射系数n2=-2.1×10-17 m2/W,三阶非线性极化率χ(3)=1.58×10-11 esu;化合物2:β=-2.4×10-10 m/W,n2=0.3×10-17 m2/W,χ(3)=0.50×10-11 esu;并测定了紫外光谱和DSC曲线。 采用密度泛函方法计算了化合物1和2的轨道能量和极化率,结果表明电子转移能在分子内部进行,说明比较易于极化,展示了良好的非线性光学性质。  相似文献   

10.
一种新的氰亚金酸根离子选择电极装置的研究   总被引:2,自引:0,他引:2  
以十六烷基三辛基氰亚金酸铵作离子交换剂制备了PVC敏感膜,并用铂丝插入0.01MKAu(CN)2-0.01MK3Fe(CN)6-0.01MK4Fe(CN)6溶液中作内参比体系,制成Au(CN)2-离子选择电极,测试了电极的各种主要性能,还测试了对十七种阴离子的电位选择性系数,并对其规律进行了讨论。  相似文献   

11.
A carbon paste electrode modified with electropolymerized fills of isonicotinic acid was developed.The modified electrode shows excellent electrocatalytic activity toward the oxidation of both dopamine(DA)and epinephrine(EP).Separation of the reduction peak potentials for dopamine and epinephrine was about 357 mV in pH 5.3 phosphate buffer solution(PBS)and the character was used for the detection DA and EP simultaneously.The peak currents increase linearly with DA and EP concentration over the range of 8.0×10-5 to 7.0×10-4 mol/L and 5.0×10-6 to 1.0×10-4 mol/L with detection limits of 2 × 10-5 and 1×10-6 mol/L,respectively.The interference studies showed that the modified electrode exhibits excellent selectivity in the presence of large excess of ascorbic acid(AA).  相似文献   

12.
利用水热合成法制备了一种基于聚乙烯亚胺的荧光碳纳米点,用光谱方法研究了其对桑色素的识别作用.结果表明,该碳纳米点对桑色素具有比率型荧光响应,且响应速度快、选择性和灵敏度高、抗干扰能力强.将桑色素加入到碳纳米点溶液中后,碳纳米点自身的荧光(460 nm)立即被猝灭,同时在555 nm处出现新的荧光发射峰并逐渐增强;其新发射峰(555 nm)与原发射峰(460 nm)的强度比值在此过程中呈线性增加.基于此,在1.0×10-6~4.0×10-5mol/L浓度范围内,可实现对桑色素的检测,该比率荧光响应非常灵敏,检出限可达3.0×10-8mol/L.另外,该碳纳米点与常见金属离子、氨基酸及其它具有类似桑色素结构的黄酮醇均不反应,显示出对桑色素的高选择性.该检测方法的荧光强度随桑色素浓度的增加而逐渐增强,并伴随着由蓝色到黄色的荧光颜色变化,可实现对桑色素的可视化检测;同时该碳纳米点还可用于稀释胎牛血清中桑色素的定量检测.  相似文献   

13.
用聚乙烯醇凝胶为基质的光导纤维铝传感器的研究   总被引:2,自引:0,他引:2  
本文将桑色素通过氰脲酰氯固定在聚乙烯醇上,以戊二醛作为交联剂,在光导纤维上制得对铝离子产生荧光响应的聚乙烯醇凝胶传感膜,这种光纤传感器对铝离子的响应时间在10s以内,在3×10-7~10-4mol/L铝浓度范围内有良好的线性关系,实验结果与理论式相吻合。  相似文献   

14.
氯化钾介质中铈(Ⅲ)的荧光特性及应用研究   总被引:4,自引:0,他引:4  
Ce3+在pH<6.2的KCl介质中受252.4nm的紫外光激发时,发射出的353.8nm荧光可用于痕量铈的测定.在pH5~6时,用Al2(SO4)3可消除Fe3+的干扰.在0~3.0×10-6mol/L范围内,荧光强度与Ce3+的浓度遵守ΔF=2.37×106C-0.001方程(n=10,r=0.9999),检测限为6.0×10-9mol/L.用于GWB07103(GSR-1)岩石成分分析的回收率为95.0%~103.2%,变异系数是4.18%(n=10);用于水系沉积物和土壤标准物质中铈含量分析,结果与标准值无显著差异.  相似文献   

15.
研究了对氮基苯磺酸在金属离子钻(Ⅱ)作为催化剂存在下,在碱性溶液中被过氧化氢氧化的化学发光行为,测定了发光光谱,最大发射波长为445nm.基于钻(Ⅱ)的催化作用建立了分析采量钻的化学发光新方法,其线性范围为5.0×10-11~5.0×10-7g/mL,检出限为0.01ng/mLGo2+,具有较好的选择性,通过对化学发光反应产物及有关反应试剂的紫外、红外和荧光光谱的测定研究,提出了氧化发光反应的机理,还对发光猝灭作用进行了讨论。  相似文献   

16.
将锂离子选择性中性载体和亲脂性pH指示剂结合在增塑的PVC膜中,pH缓冲液中锂离子浓度的变化将引起膜颜色的改变.将该膜涂覆在光电二极管光敏区并与发出锐线光的发光二极管组装在一起,构成了一种新型锂离子选择性传感装置.报道了这一传感装置的响应特性,探讨了临床分析应用的可能性.  相似文献   

17.
In this work a new Lu3+ PVC-membrane sensor based on 2,2’-dithiobis(4-methylthiazole)(TMT) has been fabricated.The sensor exhibits a Nernstian slope of 19.6±0.4 mV decade(?) in the concentration range of 1.0×106-1.0×102 mol L1 and a detection limit of 6.8×107 mol L1.It could work well in the pH range of 2.7-9.6.The selectivity of the sensor against a lot of common alkaline,alkaline earth,transition,heavy metals and specially lanthanide ions was very good.  相似文献   

18.
N1,N2-Bis[1-(2-hydroxyphenyl)methylidene]ethanedihydrazide(MEH) was used as new compound which plays the role of an excellent ion carrier in the fabrication of a Ho(Ⅲ) membrane electrode.The electrode shows a good selectivity for Ho(Ⅲ) ion with respect to most common cations including alkali,alkaline earth,transition and heavy metal ions.This electrode has a wide linear dynamic range from 1.0×10-6 to 1.0×10-2 mol/L with a Nernstian slope of 19.8±0.3 mV per decade and a low detection limit of 5.8×10-7 mol/L in the pH range of 2.5-9.8,while the response time was rapid(<10 s).The suggested sensor was applied to the determination of Ho(Ⅲ) ions in tap water and river water samples.  相似文献   

19.
郑艳洁  刘爱林  雷云  林新华 《电化学》2013,19(4):383-387
应用交流阻抗法和循环伏安法表征聚苏丹红Ⅲ/GC电极,并研究丹皮酚在该聚合物电极上的电化学行为. 实验表明,聚苏丹红Ⅲ/GC电极对丹皮酚具有良好的电催化作用,在3.0*10-7 ~ 2.2*10-5 mol·L-1浓度范围内,其差示脉冲伏安峰电流随浓度变化呈良好的线性关系,检测限为5.0*10-8 mol·L-1. 该法可用于实际样品中丹皮酚的测定,结果令人满意.  相似文献   

20.
6-苄基腺嘌呤(6-BA)属五大类植物激素中的细胞激动素类,其主要功能为促进细胞分裂,增加细胞数.植物激素的分析大多采用光度、荧光、色谱和免疫等方法[1].用电化学分析方法对6-BA进行研究,不仅可望发展一种新的分析测试方法,也可较方便地研究6-BA...  相似文献   

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