用飞秒Ti：sapphire激光测定对称型化合物的双光子吸收和上转换荧光

用800nm波长的飞秒Ti:sapphire激光测定了2个对称型噁二唑衍生物2,5-二[4-(2-N,N-二苯氨基苯乙烯基)苯基]-1,3,4-噁二唑(PASPO)与2,5-二[4-{2-N,N-二(4-溴代苯)氨基苯乙烯基]苯基}-1,3,4-噁二唑(BrPASPO)的双光子吸收和双光子激发荧光光谱,其飞秒双光子吸收截面为20.6和9.91GM,双光子泵浦上转换荧光最大波长分别在535和545nm.测定了紫外吸收、荧光光谱,研究了化合物在不同溶剂中的溶致变色效应.化合物PASPO和Br-PASPO在二氯甲烷溶液中的吸收峰分别位于412和403nm,荧光发射峰分别位于511和495nm,荧光量子产率分别为0.73和0.70.     

新型三苯胺树枝分子的合成及荧光发射性质

采用Wittig-Horner反应合成了一种新型三苯胺树枝分子1,2,4,5-四{4-{N,N-双{4-{4-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]苯乙烯基}苯基}氨基}苯乙烯基}苯(TPAB-OXA),并测定了化合物TPAB-OXA在不同溶剂中的紫外吸收光谱、荧光发射光谱及量子产率、荧光寿命.在二氯甲烷中...     

双极型均二苯乙烯发光材料的合成和光电特性

已发现三苯胺基和苯并(噁)唑是优良的有机共轭发光材料电荷传输基团.将三苯胺基作为空穴传输基团和苯并(噁)唑作为电子传输基团引入均二苯乙烯分子中,设计并合成了四个新双极小分子发光物质4-二苯氨基-4‘-(2-苯并(噁)唑)均二苯乙烯.通过光谱分析和元素分析等方法确认了其化学结构.所合成化合物的相关分析结果表明化学结构、取代基效应、溶剂环境等因素对其UV-Vis光谱、荧光光谱、荧光量子产率、电致发光谱和启亮电压都产生一定的影响.     

三苯胺多枝化合物的合成及其荧光性质

采用Heck反应合成了2个三苯胺多枝化合物N,N,N-三{5-(4-叔丁基苯基)-1,3,4-噁二唑-2-苯乙烯基-4-苯基}胺(化合物1)和N,N,N-三[4-{2-(3,5-二-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2-]苯基}-1-乙烯基}苯基}胺(化合物2),并测定了它们的吸收光谱、单光子荧光光谱和双光子荧光光谱.化合物1和2在二氯甲烷溶液中单光子荧光发射峰分别位在536和487nm.在锁模Nd:YAG激光器800nm激光照射下,化合物1和2发射出很强的双光子上转换荧光,其最大波长分别在541和518nm.     

两种有机化合物DMAHAS和DMANHAS的合成、表征和非线性光学性质

合成了两个有机化合物：反式-4-(N-羟乙基-N-乙基胺基)-4′(二甲基胺基)二苯乙烯(简称DMAHAS)和反式-4-[N-(乙基4″-硝基苯甲酰基)-N-乙基胺基]-4′-(二甲基胺基)二苯乙烯(简称DMANHAS)。用核磁、红外光谱以及元素分析进行了表征。测试了紫外吸收光谱、单光子荧光光谱和双光子荧光光谱。在800nm的飞秒脉冲激光的激发下，DMAHAS发出较强的蓝紫色上转换荧光。荧光峰位于430nm。而在相同条件下DMANHAS的荧光淬灭。     

[1,3,4]-噁二唑衍生物的固相合成及其线性、非线性光谱性质

用固相法合成了2个噁二唑衍生物类有机化合物:5-(4-叔丁基苯基)-[1,3,4]噁二唑-2-苯乙烯基-4-苯基-二苯胺 (化合物1)与9-乙基-3,6-双{5-(4-叔丁基苯基)-[1,3,4] 噁二唑-2-苯乙烯基}-咔唑 (化合物2),并测定了它们的吸收光谱、单光子荧光光谱和双光子荧光光谱.化合物1和2在二氯甲烷溶液中单光子荧光发射峰分别位于519和476nm.在锁模Nd∶YAG激光器800nm激光照射下,化合物1和2发射出很强的双光子上转换荧光,其最大波长分别在520和485nm.     

含四嗪单元的聚对苯撑乙炔类聚合物的合成及性能

通过Sonogashira偶联反应,以二(三苯基膦)二氯化钯作为催化剂,将3,6-二氯-1,2,4,5-四嗪分别与1,4-二乙炔基-2,5-二辛氧基苯和1,4-二乙炔基-2,5-二(十二烷氧基)苯交替共聚合成了主链中含四嗪单元的新型聚对苯撑乙炔类π-共轭聚合物P1、P2。经傅里叶变换红外光谱、核磁共振氢谱、紫外-可见光谱、荧光光谱、循环伏安、X射线粉末衍射、热重分析等测试手段对共聚物P1、P2进行了表征。结果表明,所得聚合物P1和P2对常用有机溶剂的溶解性不好。与P2相比,P1有一定的结晶性。P1、P2的紫外-可见最大吸收波长均在450nm处出现。P1与P2在CHCl3溶液中的最大发射峰出现在480nm处。与2-十二烷基-1,2,3-苯并三氮唑聚对苯撑乙炔类聚合物相比,P1、P2具有较高的相对荧光量子效率。循环伏安测试显示聚合物P1、P2均在0~2.0V出现明显的p-掺杂峰。     

含2-异丙基氨基-4,6-二(3,4-乙撑二氧噻基)-1,3,5-三嗪π-共轭聚合物的合成及性能

以二价钯配合物作为催化剂,将2-异丙基氨基-4,6-二(2′-溴-3,4-乙撑二氧噻基)-1,3,5-三嗪分别与1,4-二乙炔基-2,5-二辛氧基苯、1,4-二乙炔基-2,5-二(十二烷氧基)苯、2,7-二(4,4,5,5-四甲基硼烷基)-9,9-二辛基芴交替共聚合成了3种π-共轭聚合物P1,P2和P3。经傅里叶变换红外光谱、氢核磁共振谱、紫外-可见光谱、荧光光谱、循环伏安法、X射线粉末衍射和凝胶渗透色谱等测试手段对其进行了表征,并对聚合物在CHCl3溶液的酸致变色行为进行了研究。结果表明,得到的聚合物在CHCl3中的紫外-可见最大吸收波长分别在443nm和431nm处出现。在CHCl3溶液中聚合物P1,P2和P3最大发射峰分别位于507nm,511nm和543nm,其聚合物薄膜的最大发射波长分别为573nm,557nm和559nm。与P1和P2相比,P3的酸致变色敏感性高于2个数量级。聚合物P1和P2均在-2.0~0V出现n-掺杂峰。聚合物X射线衍射谱图显示聚合物均有一定的结晶性。     

苯腙类光电材料的合成及其性能

以三苯胺、苯肼和芴酮为原料,通过甲酰化、亲核加成反应合成了4-(N,N-二苯基)氨基苯甲醛苯腙(PABPD)、4-(N,N-二苯基)氨基苯甲醛-3,5-二硝基苯腙(PABNPD)和芴酮苯腙(FPD)三种苯腙类有机光电材料。采用1 HNMR、FTIR和元素分析对该系列化合物的结构进行了表征,并考察了该类化合物的紫外-可见吸收光谱、荧光发射光谱、电化学性质及热稳定性质。实验结果表明:三种目标化合物的最大紫外吸收峰分别出现在374、422和395nm,且PABPD可在445nm附近发出较强的蓝色荧光,PABNPD可在543nm附近出现较强的绿色荧光,FPD可在465nm附近出现较弱的蓝色荧光;TG分析结果表明三种目标化合物具有较好的热稳定性;采用循环伏安法测得三种目标化合物的电离势分别为4.91、5.15和5.04eV,说明PABPD相对于PABNPD和FPD具有更为优良的空穴传输性能,因此PABPD是一种具有潜在应用前景的空穴传输材料和蓝光发光材料。     

一种有机染料的双光子荧光性质及反应中间体的晶体结构

合成了一种新的有机染料1,2,4,5-四(4-吡啶乙烯基)苯1,2,4,5-tetrakis(4-pyridylvinyl)benzene(简称为TVPB)并测试了其双光子荧光性质.溶剂缓慢挥发法得到了其反应中间体1,2,4,5-四(二甲氧基膦酰甲基)苯1,2,4,5-tetra (dimethoxyphosphorylmethyl)benzene(简称为TDMPMB)的晶体.用X射线四圆衍射仪对晶体结构进行了解析.     

聚对苯乙炔二元共聚物P(DHOPV-co-MOBOPV)的制备与性能

采用强碱诱导的脱氯化氢缩合聚合法合成一种可溶性烷氧基取代聚对苯乙炔二元共聚物聚(2,5-二己氧基对苯乙炔-co-2-甲氧基-5-丁氧基对苯乙炔)[P(DHOPV-co-MOBOPV)].研究表明,P(DHOPV-co-MOBOPV)在可见光区具有较强吸收,其最大吸收波长位于500 nm;当双氯苄物质的量比为l:1和6:...     

Diode-end-pumped,electro-optically Q-switched Nd:YVO4 slab laser and its second-harmonic generation

We describe the operation of a near-diffraction-limited, 1,064-nm electro-optically Q-switched Nd:YVO4 slab laser that is end pumped by laser-diode stacks and its efficient second-harmonic generation by using a lithium triborate (LBO) crystal. The energy per pulse of 3.6 and 0.8 mJ and pulse widths of 5 and 13.5 ns were obtained at repetition of 5 and 40 kHz, respectively. With a LBO crystal, a maximum output power of 15.6 W at 532 nm was obtained at the repetition rate of 40 kHz, the corresponding conversion efficiency was 60%, and the pulse width was 11.3 ns. At 10 kHz, the pulse energy of 532 nm was 1.2 mJ, and the pulse width was 5 ns.     

Intracavity second-harmonic generation at 320 nm of an actively Q-switched Pr:LiYF4 laser

We demonstrate pulse laser operation of a Pr:LiYF(4) laser pumped by InGaN laser diodes (444 nm) using an acousto-optic modulator. We obtained a maximum laser peak power of 167 W (4 μJ/pulse) with a pulse width of 24 ns at an 11 kHz repetition rate for a 63 nm wavelength. Employing an 8 mm long lithium triborate nonlinear crystal in the laser cavity, we obtained a maximum peak power of 55 W (2.7 μJ/pulse) at 320 nm, which corresponds to a conversion efficiency of 69% with respect to the fundamental laser energy. The UV laser pulse width was 36 ns.     

Synthesis,crystal structure and thermal analysis of a new stilbazolium salt crystal

A new organic crystal of 4-N, N-dimethylamino-4′-N′-methyl-stilbazolium benzene sulfonate (DASBS) was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) with the benzene sulfonate replacing p-toluenesulfonate. Single crystal XRD demonstrated that the crystal structure of DASBS·H₂O was triclinic. The thermal analysis of this new crystal was also conducted, and the melting point was obtained to be 232°C.     

新型含氟8-羟基喹啉锌配合物的合成及光学性能研究

设计合成了3种新型含单氟8-羟基喹啉衍生物配体:(E)-2-[2-(2-氟代苯基)乙烯基]-8-羟基喹啉(4a)、(E)-2-[2-(3-氟代苯基)乙烯基]-8-羟基喹啉(4b)、(E)-2-[2-(4-氟代苯基)乙烯基]-8-羟基喹啉(4c)及其相应的锌配合物(5a)、(5b)、(5c),利用1 H-NMR、IR、MS、元素分析确认了其结构。测定了它们在DMF溶液中的荧光性质;荧光光谱显示化合物4a、4b、4c在DMF溶液中的λmax分别是505nm、487nm、513nm;5a、5b、5c的λmax分别是559nm、598nm、588nm,荧光光谱显示氟基位置的改变可以调控8-羟基喹啉锌配合物的发光性质。     

Gold nanoshell photomodification under a single-nanosecond laser pulse accompanied by color-shifting and bubble formation phenomena

Laser-nanoparticle interaction is crucial for biomedical applications of lasers and nanotechnology to the treatment of cancer or pathogenic microorganisms. We report on the first observation of laser-induced coloring of gold nanoshell solution after a one nanosecond pulse and an unprecedentedly low bubble formation (as the main mechanism of cancer cell killing) threshold at a laser fluence of about 4?mJ?cm(-2), which is safe for normal tissue. Specifically, silica/gold nanoshell (140/15?nm) suspensions were irradiated with a single 4?ns (1064?nm) or 8?ns (900?nm) laser pulse at fluences ranging from 0.1?mJ?cm(-2) to 50?J?cm(-2). Solution red coloring was observed by the naked eye confirmed by blue-shifting of the absorption spectrum maximum from the initial 900?nm for nanoshells to 530?nm for conventional colloidal gold nanospheres. TEM images revealed significant photomodification of nanoparticles including complete fragmentation of gold shells, changes in silica core structure, formation of small 20-30?nm isolated spherical gold nanoparticles, gold nanoshells with central holes, and large and small spherical gold particles attached to a silica core. The time-resolved monitoring of bubble formation phenomena with the photothermal (PT) thermolens technique demonstrated that after application of a single 8?ns pulse at fluences 5-10?mJ?cm(-2) and higher the next pulse did not produce any PT response, indicating a dramatic decrease in absorption because of gold shell modification. We also observed a dependence of the bubble expansion time on the laser energy with unusually very fast PT signal rising (～3.5?ns scale at 0.2?J?cm(-2)). Application of the observed phenomena to medical applications is discussed, including a simple visual color test for laser-nanoparticle interaction.     

Synthesis and characterization of environment friendly and multifunctional Fe3O4 magnetic nanoparticles

In this study, the size-uniform (5-6 nm), nearly spherical, and well-dispersed aqueous Fe3o4 magnetic nanoparticles were prepared by an improved chemical coprecipitation method. The DDAT-terminated (S-1-Dodecyl-S'-(alpha,alpha'-dimethyl-alpha"-acetic acid) trithiocarbonate) polymethacrylic (PMA-DDAT) was chosen as the apt surfactant, and the terminal DDAT can be used as a high efficient RAFT chain-transfer agent for further functionalization. Then, the functionalized Fe3O4 reacted with 4-amino-2,2,6,6-tetramethyl-piperidine-oxyl (4-NH2-TEMPO) to give the spin labeling magnetic nanoparticles. Finally, the multifunctional MNPs was characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR), Fourier transform infrared spectrometer (FT-IR), and vibrating-sample magnetometer (VSM). The obtained highly water-soluble, superparamagnetic, and multifunctional magnetic nanoparticles should find potential applications in biomedical research.     

π电子共轭键结构对材料非线性光学性能影响研究

合成了具有不同π电子共轭键3个新的有机光学材料4-(吡啶-4-乙烯),4'-(N,N-二羟乙基氨基)二乙烯苯(a),N-((4-(N,N-二羟乙基氨基)-苯亚甲基)-4-(吡啶-4-乙烯)苯胺(b)和4-(吡啶-4-乙烯),4'-(N,N-二羟乙基氨基)偶氮苯(c),使用脉宽8ns波长532nm调Q倍频ns/ps Nd:YAG脉冲激光系统测试了它们的非线性光学性能,研究了分子结构与非线性光学性能之间的关系.结果显示这些化合物具有大的三阶非线性光学系数,这可能来源于它们长的D-π-A共轭电子结构;以N=N双键为共轭键的化合物的非线性光学性能优于以C=N或G=C双键为共轭键的化合物.     

A Fluorogenic Reagent, 7-Phenylsulfonyl-4-(2,1,3-benzoxadiazolyl) Isocyanate for Alcohols, with Development Based on the Empirical Method for Prediction

During the course of our studies, we found the relationship between the fluorescence characteristics (the fluorescence intensity and the maximum excitation and emission wavelengths) of benzofurazan compounds and the sum and difference of Hammett substituent constants (σp) at the 4- and 7- positions. This prompted us to design a useful fluorogenic derivatization reagent having the benzofurazan skeleton for alcohols along this line of thought. Accordingly, the fluorogenic derivatization reagents, which have no fluorescence themselves, 7-N,N-dimethylaminosulfonyl-4-(2,1,3-benzoxadiazolyl) isocyanate (DBD-NCO), 7-phenylsulfonyl-4-(2,1,3-benzoxadiazolyl) isocyanate (PSBD-NCO), and 7-methylsulfonyl-4-(2,1,3-benzoxadiazolyl) isocyanate (MSBD-NCO), were synthesized. Among the derivatives derived from the three reagents, that from PSBD-NCO was most strongly fluorescent. PSBD-NCO reacted with 1-octanol within 4 h in acetonitrile solution in the absence of a catalyst at 60 °C. The derivatives with four alcohols (1-octanol, 1-nonanol, 1-decanol, and 1-undecanol) were separated on a reversed-phase column and detected fluorimetrically at 490 nm with the excitation at 368 nm. The detection limits were at the 10-femtomole level. PSBD-NCO was superior to other fluorescent-labeling reagents with regard to the avoidance of the interfering peaks derived from the reagents themselves and degradation products in the chromatogram. The effectiveness of our approach is disccussed in terms of the development of new fluorogenic reagents.