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1.
采用脉冲激光沉积(PLD)法在Si(111)衬底上制备了Eu3+,Li+共掺杂的ZnO薄膜,分别在450,500,550和600℃条件下进行退火,退火气氛为真空。利用X射线衍射(XRD)仪和荧光分光光度计研究了退火温度对薄膜结构和光致发光(PL)的影响。研究结果表明,Eu3+,Li+共掺杂的ZnO薄膜具有c轴择优取向,Eu3+,Li+没有单独形成结晶的氧化物,均以离子形式掺入ZnO晶格中。PL谱中有较宽的ZnO基质缺陷发光,ZnO基质与稀土Eu3+之间存在能量传递,但没有有效的能量传递。随着退火温度的增加,薄膜发光先增强后减弱,退火温度为550℃时发光最强。当用395 nm的激发光激发样品时,仅观察到稀土Eu3+在594 nm附近的特征发光峰,但发光强度随退火温度变化不明显。  相似文献   

2.
结晶紫共振光散射法测定脱氧核糖核酸   总被引:19,自引:0,他引:19  
研究了三苯甲烷类碱性染料结晶此与DNA作用的共振光散射光谱,在pH9.2-10.5的范围内,加入DNA导致结晶紫共振光散射增强,在512nm处,存在一共振光散射增强峰,其强度与DNA的浓度呈线性关系,据此建立了一种测定DNA的菜振光散射法,方法的线性范围为0-900ng/mL,检出限为5.02mg/mL.已用于混合样品中的DNA的测定.  相似文献   

3.
The J-aggregation behavior of diprotonated tetrakis(4-sulfonatophenyl)porphyrin (H2TPPS4(2-)) in aqueous solution in the presence of the hydrophilic ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF4) was investigated in detail using UV-vis absorption spectroscopy, fluorescence spectroscopy, resonance light scattering (RLS) spectroscopy, Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. With the addition of bmimBF4, increasing peaks appeared at a wavelength of 490 nm in the absorption spectra to account for the formation of H 2TPPS4(2-) J-aggregates. In addition, the experimental results also showed decreased fluorescence emission, enhanced RLS signals, intensified Raman scattering peaks, and the disappearance of NMR signals to further indicate that porphyrin J-aggregates exist in the studied system. NMR shifts of bmimBF 4 toward high field occurred corresponding to H2, H4, and H5 in the cationic imidazolium ring (bmim+), suggesting that bmim+ enters the magnetic shielding domain of the anionic phenyl sulfonate ion owing to the association process between the "large" cation and anion. Additionally, the fact that the absorption spectral shifts occurred in the nonprotonated porphyrin TPPS4(4-) further indicates the existence of the ion association effect of bmim+, which functions as an important factor in porphyrin aggregation.  相似文献   

4.
柑桔溃疡菌的共振散射光谱   总被引:3,自引:0,他引:3  
研究了柑桔溃疡菌的共振散射光谱,在330、425、465和695 nm产生四个共振散射峰.当激发波长为330 nm (9.09×1014 Hz)时,溃疡菌溶液在330 nm(9.09×1014 Hz)、660 nm(1/2×9.09×1014 Hz)和990 nm(1/3×9.09×1014 Hz)分别产生一共振散射峰和1/2、1/3两个分频散射峰;当激发波长为465 nm(6.45×1014 Hz)时,在456 nm(6.45×1014 Hz)和930 nm(1/2×6.45×1014 Hz)分别产生一个共振散射峰和一个1/2分频射峰; 当激发波长为930 nm(3.23×1014 Hz)时,在930 nm (3.23×1014 Hz)、620 nm(3/2×3.23×1014 Hz)、465 nm(2×3.23×1014 Hz) 和310 nm (3×3.23×1014 Hz)分别产生一个共振散射峰,一个3/2分频共振散射峰,一个2倍频共振散射峰和一个3倍频共振散射峰.柑桔溃疡菌是一种非线性散射光学介质.分频散射和倍频散射峰与共振散射峰具有相似的散射行为.  相似文献   

5.
曙红Y的共振光散射与共振荧光   总被引:2,自引:0,他引:2  
研究了曙红Y(EY)的共振散射光谱、荧光光谱和吸收光谱,讨论了共振光散射与共振荧光的区别与联系。在EY水溶液三维荧光等高线光谱图中,瑞利散射线与荧光等高线有部分相交。EY的共振散射峰(525nm)介于荧光激发峰(514nm)和发射峰(536nm)之间。由光偏振实验,测得EY共振散射光谱525nm处的偏振度P=0.20。上述实验结果证明,EY的共振散射峰主要是共振荧光。在改变pH的实验中发现,EY共振光散射增强是由于酸碱平衡的移动导致荧光型体的形成。由于自吸收的影响,共振散射光强度与EY浓度之间不是严格的线性关系。  相似文献   

6.
韩涛  杨佳  唐英  张进  涂铭旌 《应用化学》2011,28(10):1213-1217
在乙二醇中,以聚乙烯吡咯烷酮(PVP)为分散剂,抗坏血酸(VC)为还原剂和抗氧化剂,还原CuSO4制得铜胶体溶液。 通过XRD、UV-Vis与共振光散射(RLS)光谱对铜胶体进行表征。 结果表明,铜胶体为面心立方晶体结构的0价铜,在592~602 nm呈现典型的等离子共振吸收峰,体系具有明显的RLS特征,最大散射波长在468 nm。 考察了反应条件、体系的稳定性与共存离子对乙二醇中铜胶体RLS的影响。 结果表明,适宜的反应条件为:试剂按照VC、CuSO4和PVP的加入顺序,3种物质量的比按照n(VC)/n(Cu2+)=15、n(PVP-K30)/n(Cu2+)=1.4;反应温度60 ℃;反应时间1 h,反应得到的铜胶体可稳定放置1 d。 在适宜条件下,ρ(Cu2+)在5.12~12.8 mg/L范围内与散射光强度(ΔIRLS)成正比,回归方程为ΔI=7 420.2ρ-631.8(r=0.9962),检出限(3σ)为0.63 μg/L。 0.64 mg/L MnSO4、CdSO4和ZnSO4,1.28 mg/L KI,64 mg/L Na2CO3和Ca(OH)2,960 mg/L CH3CH2OH,640 mg/L CH3OH和320 mg/L CH3CH2CH2OH均不干扰10 mg/L Cu2+溶液的测量。 由此建立一种利用RLS光谱测定乙二醇中铜离子的简便方法。  相似文献   

7.
灿烂甲酚蓝共振光谱散射法测定脱氧核糖核酸   总被引:18,自引:0,他引:18  
刘晨  陈小明 《分析化学》2001,29(6):685-688
研究了灿烂甲酚蓝与脱氧核糖核酸(DNA)作用的共振光散射光谱,在pH=10.8-11.5的范围内,DNA的加入导致灿烂甲酚蓝共振光散射的增强,在347nm处,存在一共振光散射增强峰,其强度与DNA的浓度呈线性关系,据此建立了一种测定DNA的共振光谱散射法。该方法的线范围为80-100μg/L,检出限为23.3μg/L.  相似文献   

8.
建立了一种以金纳米微粒为探针共振光散射(RLS)法测定维生素B4的新方法.在弱酸性介质中(pH 4.2),金纳米微粒在635 nm有一最大共振散射峰.加入微量维生素B4后,金纳米微粒与维生素B4通过静电引力结合.形成了粒径较大的聚集体,导致RLS强度显著增强.研究了体系的共振光散射光谱特征和反应适宜条件,探讨了共振光散射增强的机理.结果表明,维生素B4质量浓度在0.1~5.0μg/mL 时与散射强度(△I)呈线性关系,检出限(3σ)为12.0 ng/mL,相对标准偏差(RSD)为2.2%.该方法已用于片剂中维生素B4的测定.  相似文献   

9.
YF3:Eu3+纳米纤维/高分子复合纳米纤维的制备与表征   总被引:1,自引:1,他引:0  
采用静电纺丝技术制备了Y2O3:Eu3+纳米纤维,使用NH4HF2为氟化剂,经双坩埚法氟化和脱氨后得到YF3:Eu3+纳米纤维,再采用静电纺丝技术制备了YF3:Eu3+纳米纤维/PVP复合纳米纤维. XRD分析表明,立方相的Y2O3:Eu3+氟化后,得到了正交相的YF3:Eu3+纳米纤维,空间群为Pnma;YF3:Eu3+纳米纤维/PVP复合纳米纤维具有明显的YF3:Eu3+的衍射峰. SEM分析表明,YF3:Eu3+纳米纤维与YF3:Eu3+纳米纤维/PVP复合纳米纤维的直径分别为91±11 nm、319±43 nm,表面光滑. 用Shapiro-Wilk方法检验,纤维直径属于正态分布. 荧光光谱分析表明,YF3:Eu3+纳米纤维和YF3:Eu3+纳米纤维/PVP复合纳米纤维的最强发射峰均位于588 nm和595 nm,属于Eu3+的5D0→7F1跃迁,表明Eu3+占据YF3基质中Y3+晶格点的C2对称格位. PVP对YF3:Eu3+发光峰位没有影响,但发光强度降低;YF3:Eu3+的含量与YF3:Eu3+纳米纤维/PVP复合纳米纤维的发光强度成线性关系.  相似文献   

10.
In this paper, we used resonance light scattering (RLS) spectroscopy to study the interaction between thiol-containing pharmaceutical-thiamazole and gold colloid. At pH 5.2, the resonance light scattering spectrum of gold nanoparticles has a maximum peak at 555 nm and the RLS intensity is enhanced by trace amount of thiamazole due to the interaction between thiamazole and gold colloid. The binding of colloidal gold to thiamazole results in ligand-induced aggregation of colloidal gold, which was characterized by RLS spectrum, ultraviolet-visible (UV-Vis) spectrum, and transmission electron microscopy (TEM). Based upon the study, we proposed a highly sensitive, gold colloid-based assay using RLS spectrum to detect pharmaceuticals for the first time. The mechanism of binding interaction between Au colloid and thiamazole was also discussed.  相似文献   

11.
The interaction of Acid chrome blue K (ACBK) with nucleic acids in weak basic medium was studied in the presence of cetyltrimethylammonium bromide (CTMAB) based on the measurements of resonance light scattering (RLS), UV-vis, NMR spectra, etc. In hexamethylene tetramine (HMTA) buffer (pH 7.45), ACBK and nucleic acids react with CTMAB to form a ternary complex, which results in strong enhanced RLS signals characterized by four peaks at 285, 335, 405.5 and 548nm. Mechanistic studies show that the enhanced RLS stems from the aggregation of ACBK on nucleic acids through the bridged and synergistic effect of CTMAB. With the enhanced RLS signals at the best wavelength at 335nm, the enhanced RLS intensity is proportional to the concentration of nucleic acids in a wide range. The lowest limit of determination was 7.52ngml(-1), three synthetic samples were analyzed satisfactorily. And the combined points of the anionic dye ACBK with nucleic acids-CTMAB have been tentatively confirmed through the measurement of 1H NMR spectra.  相似文献   

12.
在弱酸性介质中, 四羧基铝酞菁和硫酸庆大霉素本身的共振散射(RLS)均较弱, 但两者相互作用形成离子缔合物时, RLS显著增强, 在350~500 nm之间有一个强散射带, 最大散射峰位于401 nm. 而且散射强度与硫酸庆大霉素的浓度成正比, 可用于硫酸庆大霉素的定量测定, 线性范围为0.025~1.5 μg/mL, 检出限0.018 μg/mL. 方法可用于市售硫酸庆大霉素注射液含量的测定.  相似文献   

13.
在卵磷脂体系中合成EuF3纳米线   总被引:1,自引:0,他引:1  
利用大豆卵磷脂在水中自发形成的囊泡作模板, 先制备出含有Eu3+的卵磷脂乳液, Eu3+与卵磷脂亲水头部的磷氧键相结合形成Eu—O—P键, 经用NH4F沉淀后制得前驱体, 该前驱体在600 ℃灼烧, 得到EuF3纳米线, 其直径约为10-20 nm. 通过对各阶段产物的荧光光谱、傅里叶变换红外(FTIR)光谱、热重-差热分析(TG-DTA)、透射电镜(TEM)等的对比分析, 确认形成了Eu—O—P键, 所得到的纳米线是多晶相EuF3.  相似文献   

14.
橙红色荧光粉BaZnP2O7∶Eu3+的制备与发光特性   总被引:3,自引:0,他引:3  
采用高温固相法合成了BaZnP2O7∶Eu3+荧光粉, 并对其发光性质进行了研究.  相似文献   

15.
The interaction between resveratrol and DNA has been studied by resonance light scattering (RLS) technique. In strongly acidic solution, resveratrol has a maximum peak at 368 nm and the RLS intensity is remarkably enhanced by trace amounts of DNA due to its interaction with resveratrol. Based on this, a novel assay for nucleic acids has been developed. The characteristics of RLS, fluorescence and UV-VIS absorption spectra, the influential factors and optimum conditions of the reaction have been studied. The enhanced RLS intensity at 368 nm is proportional to the concentration of DNA within the range of 0–1600 μg/L for calf thymus DNA. The determination limit (3σ) is 5.2 ng/mL. The study of foreign substance effect on the determination of DNA indicates that most of metal ions have little effect on the determination of DNA. Three synthetic samples of DNA were analysed with satisfactory results. The results show that the proposed method is very sensitive, convenient, rapid and reproducible.  相似文献   

16.
Sr2MgSiO5∶Ce3+的发光性质研究   总被引:5,自引:1,他引:4  
报道了Sr2MgSiO5∶Ce3+荧光粉的发光性质.  相似文献   

17.
As a resonance light scattering (RLS) probe, the polyelectrolyte polymethacrylic acid (PMAA) was applied in this assay. The bovine serum albumin (BSA) and human serum albumin (HSA) were determined by the electrostatic interaction of PMAA and proteins. At pH 3.8 Na(2)HPO(4)-citric acid buffer solution, the RLS intensities of PMAA-BSA (HSA) system were greatly enhanced. The characteristic peaks were appeared at the wavelength 320, 546 and 594 nm. The optimization conditions of the reaction were also examined and selected. Under the selected conditions, the RLS intensities were proportional to the protein concentrations in the range of (0.0200-2.00) x 10(-6) mol/L for BSA and (0.0200-2.40) x 10(-6) mol/L for HSA. The influences of some foreign substances were also examined. The synthetic samples containing proteins and some real samples were analyzed and the results obtained were satisfactory.  相似文献   

18.
以化学沉淀法制备单相的铕离子掺杂硼铝酸盐红色荧光粉YAl3(BO3)4∶Eu3+,考察了焙烧温度、掺铕量等因素对材料性能的影响,用X射线衍射、扫描电镜、激发光谱和发射光谱对荧光粉的结构、形貌和发光性能进行了表征.以尿素为沉淀剂,900℃焙烧沉淀前驱体可得到单相荧光粉YAl3(BO3)4∶Eu3+,反应温度比传统高温固相法降低了300℃;沉淀法制备的荧光粉粒径分布范围小,无团聚现象,粒径约300nm.掺铕量为10%(物质的量比)时发光强度最大.在260nm的紫外光激发下,Eu3+的5 D0→7 F2的电偶极跃迁最强,发射光为618nm的红光.  相似文献   

19.
Ce3+,Tb3+,Eu3+共掺杂Sr2MgSi2O7体系的白色发光和能量传递机理   总被引:1,自引:0,他引:1  
通过正交试验,采用高温固相法制备了Sr2-x-y-zMgSi2O7∶xCe3+,yTb3+,zEu3+系列样品.使用X射线衍射仪和荧光光谱仪表征了样品的物相和发光性质,并讨论了Ce3+-Tb3+-Eu3+共掺杂Sr2MgSi2O7体系中的能量传递过程.实验结果表明,在327 nm波长激发下,所合成荧光粉的发射峰主要位于387 nm(蓝紫)、542nm(绿)和611 nm(红)处;分别以387,542和611 nm为监控波长,所得激发光谱显示荧光粉在327 nm处有最好的激发.在327 nm光激发下,系列样品发光进入白光区.最优化的荧光粉为Sr1.91MgSi2O7∶0.01Ce3+,0.05Tb3+,0.03Eu3+,其色坐标为(0.337,0.313),是一种潜在的发光二极管(LED)用白色荧光粉.  相似文献   

20.
金纳米粒子的非线性共振散射及光强度函数研究   总被引:12,自引:0,他引:12  
液相金纳米粒子在320nm、470nm、580nm720nm处产生四个共振散射峰。它是一种非线性光学介质,当入射光的频率v不同时可获得金纳米粒子的2v倍频、v/2分频、v/3分频、2v/3 分频、3v/2分频散射峰。探讨了影响液相金纳米粒子散射光信号强度I(λ)的主要因素即散射光能量分布、粒径d、△λ(λem-λex)和散射光辐射度Rλex。给出了共振散射光强度与△λ之间的高斯分布函数。建立了一个合理的金纳米粒子的共振散射光强度函数。  相似文献   

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