HoYb:YVO4的上转换发光研究

研究了960nm激光激发下HoYb双掺钒酸钇晶体HoYb:YVO4的直接上转换增敏发光,发现了Ho3+离子的上转换发光现象,HoYb:YVO4晶体的上转换发光是5F5→5I8最强,而5S2→5I8相对小了一个数量级,这是由于YVO4晶体既有很强的振子强度又有很大的多声子无辐射弛豫造成的. 关键词： 上转换发光 直接增敏(敏化) 钒酸钇YVO4晶体 Ho3+离子     

Ce3+离子敏化Eu3+∶Cr3+∶Sm3+∶YAG外延层的荧光现象

对Ce3+ ∶Eu3+ ∶Cr3+ ∶Sm3+ ∶YAG处延层中的荧光敏化现象进行了报道和分析 ,在较高浓度的Ce3+ 离子掺杂时 ,外延层在蓝色、绿色波段出现了新的荧光谱线 ,可解释为在Ce3+ 离子敏化作用下 ,Eu3+ 离子产生了由高位激发态能级5Di(i=1,2 ,3)直接到基态能级7Fj(j =0 ,1,2 ,3)的辐射跃迁过程 ,并且这种Ce3+ ∶Eu3+ ∶Cr3+ ∶Sm3+ ∶YAG外延层还是一种新颖的白色单晶荧光材料。     

SPS法研究ZnTPP对TiO_2的光谱敏化

本文利用表面光电压谱(Surface Photovohage spectroscopy,简称SPS)研究了ZnTPP对TiO_2粉末的光谱敏化,发现用ZnTPP修饰后的TiO_2(金红石和锐钛矿)粉末在可见区420、550和590nm附近有三个光伏响应带,它们分别对应于ZnTPP的Soret、Q(1,0)和Q(0,0)带。经过严格的实验和分析,证明这三个带是由ZnTPP对TiO_2的敏化光电压引起的,而不是ZnTPP自身的光伏响应。在敏化效果上,亚稳的锐钛矿优于金红石。同时,我们对这种光敏表面的光诱导电荷转移机制和SPS作为一种研究光谱敏化方法的可行性进行了讨论。     

Photocatalytic Properties of Titanium Dioxide Heterostructures with Cyanine Dyes and Polyepoxy Propylcarbazole

We have obtained novel photosensitive materials containing a semiconductor photocatalyst and a dye sensitizer. We have studied the activity of the latter in the reaction of photoreduction of methylene blue, and we consider possible mechanisms for the photocatalytic effect.     

Electron capture detector response to low electron affinity aromatic hydrocarbons using positive ion stabilization and alkyl chloride sensitization

The electron capture detector (ECD) response to numerous aromatic hydrocarbons of low electron affinity (EA) is shown to be detrimentally affected by two processes which compete with and typically overwhelm the electron capture reactions of these molecules. It is shown that the effects of these two undesired reactions can be eliminated by the permanent addition of trimethylamine and one of several alkyl monochlorides to the detector make-up gas. These modifications of the detector gas result in greatly increased sensitivity, increased linearity, and increased reproducibility of response. A kinetic model for the ECD responses of low EA resonance capture molecules is developed which appears to explain these improvements.     

Sm~(3 )在硼酸盐玻璃中的发光及Bi~(3 )对Sm~(3 )的敏化作用

早在六十年代,人们为了寻找较好的激光玻璃,曾对Sm~(3 )离子掺杂的玻璃中的光谱进行过研究。为了探寻新型的激光,发光玻璃,又进一步研究了Sm~(3 )在玻璃中的发光和敏化。我们以寻找一种高亮度,低成本的发光玻璃为目的,研究了基质玻璃组成,敏化离子及其浓度对Sm~(3 )发光性质的影响。 选择B_2O_3-BaO-M_mO_n(M_mO_n=Li_2O,Na_2O,K_2O,MgO,CaO,SrO)玻璃体系,所用原料的纯度皆为分析纯以上,用陶瓷坩埚在1250℃掺杂氧化钐(纯度均大于99％),玻璃的荧光谱和激发光谱,用MPF-4型荧光分光光度计测定。     

一种基于形成杂多核络合物的荧光增敏效应的研究 Ⅲ.锰(Ⅱ)、钴(Ⅱ)的混合荧光增敏及其连续测定

本文研究了Mn~(2+)和Co~(2+)对7-(8-羟基-3,6-二磺基萘偶氮)-8-羟基喹啉-5-磺酸-硼砂反应体系的混合荧光增敏作用。实验条件下,荧光增敏强度满足线性加和关系的范围是:Mn~(2+)浓度0～2.9×10~(-7)mol/L;Co~(2+)浓度0～8.8×10~(-7)mol/L;总浓度不超过1.0×10~(-6)mol/L。检出限量为Mn~(2+)4.5×10~(-9)mol/L和Co~(2+)1.4×10~(-8)mol/L。实现了Mn~(2+)和Co~(2+)的连续测定。     

一种基于形成杂多核配合物的荧光增敏效应的研究（Ⅱ）──钴（Ⅱ）－7－（8－羟基－3，6－二磺基萘偶氮）－8－羟基喹啉－5－磺酸－硼（Ⅲ）三元体系的荧光性质及其分析应用

一种基于形成杂多核配合物的荧光增敏效应的研究（Ⅱ）──钴（Ⅱ）－７－（８－羟基－３，６－二磺基萘偶氮）－８－羟基喹啉－５－磺酸－硼（Ⅲ）三元体系的荧光性质及其分析应用熊国华，刘虹，俞英，黄坚锋（九江师范专科学校化学系，九江，３３２０００）（江西大学实...     

Novel peripherally functionalized seco-porphyrazines: synthesis, characterization and spectroscopic evaluation

Co-macrocyclizations of 2,3-dipropylmaleonitrile and 2,3-di-(4-(methoxycarbonyl)phenyl)maleonitrile, respectively, with N,N′-dibenzyl-N,N′-di-(11-tetrahydropyranyloxy-3,6,9-trioxo-undecyl))maleonitrile and N,N,N′,N′-tetramethylmaleonitrile were used to prepare derivatives of the 4,5-diamino-porphyrazine systems including the zinc(II) complexes. Subsequent oxidation of the macrocycles with potassium permanganate gave the corresponding seco-porphyrazines. These were shown to be efficient sensitizers for the production of singlet oxygen (Φ_Δ=0.15-0.57) by the determination of their photophysical properties.     

Syntheses of mixed ligands complexes of Ru(II) with 4,4′-dicarboxy-2,2′-bipyridine and substituted pteridinedione and the use of these complexes in electrochemical photovoltaic cells

The synthesis, spectral and photoelectrochemical studies of mixed ligand complexes of [Ru(dcbpy)₂(LL)]Cl₂, where LL=2,4-(1,3-N,N′-dimethyl)pteridinedione (DMP), 6,7-dimethyl-2,4-(1,3-N,N′-dimethyl)pteridinedione (MDMP), 6,7-diphenyl-2,4-(1,3-N,N′-dimethyl)pteridinedione (PhDMP), dibenzo[h,j]-(1,3-N,N′-dimethyl)isoalloxazine (BIAlo), 6,7-bis(pyrid-2-yl)-2,4-(1,3-N,N′-dimethyl) pteridinedione (PyDMP) were carried out. These complexes were attached to sol–gel processed TiO₂ electrodes and the photocells fabricated were illuminated with polychromatic radiation in the presence of I₂/I₃⁻ as redox electrolyte. The incident photon to current conversion efficiency determined was found to be 20–48%.