2，6-二（2’-芳基-1’，3’，4’-噁二唑基）吡啶的合成与光谱性质

合成了3个2,6-二(2'-芳基-1',3',4'-(噁)二唑基)吡啶化合物,用1HNMR、FT-IR、MS对其结构进行了表征.研究了它,们的UV-Vis吸收光谱、荧光光谱.紫外.可见吸收光谱表明:目标化合物在278～309 nm出现最大吸收峰;荧光光谱表明:目标化合物在DMF溶液中发射强的紫色荧光,在364～398 nm出现最大发射峰;固体发射强的紫蓝色荧光,在376～414 nm出现最大发射峰.     

含1,3,4-噁二唑与苯或吡啶共轭化合物的合成与表征

以间苯二甲酸和2,6-吡啶二甲酸为原料,经酯化、氨解、关环和取代4步反应合成了1,3-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-苯和2,6-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-吡啶,利用IR、1HNMR及MS对其结构进行表征。在304nm波长光激发下,1,3-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-苯(1.0×10-5mol/L的DMF溶液)在357 nm发射荧光;在281 nm波长光激发下,2,6-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-吡啶(1.0×10-5mol/L的DMF溶液)在354 nm发射荧光。结果表明,两种目标化合物均具有良好的荧光性能。     

含呋喃环双噁二唑的合成与光谱性质

合成了6个3,4-二(2’-芳基-1’,3’,4’-噁二唑基)呋喃,化合物的结构经1H NMR、FTIR、MS表征。初步发光性能表明,在272～293 nm出现最大紫外-可见吸收峰;在DMF溶液中,341～375 nm出现最大荧光发射峰,是一类紫色发光材料。     

2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯的合成和非线性光学性质

报道了具有典型D-A-D型共轭结构的反式2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯(DCHO)的合成。用核磁、红外和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、双光子荧光光谱及双光子吸收截面。在800 nm的飞秒脉冲激光激发下,标题化合物发出很强的绿色上转换荧光。化合物2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯的最大吸收波长、单光子发射波长、最大双光子荧光波长、荧光量子产率、双光子吸收系数及双光子吸收截面分别是393 nm、470 nm、475 nm、0.12、0.8 cm/GW、270 GM。这些数据表明,对位甲氧基的D-A-D型化合物具有较好的双光子吸收性能,DCHO是双光子荧光显微与成像应用的一个良好的候选材料。     

2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯的合成和非线性光学性质

报道了具有典型D-A-D型共轭结构的反式2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯(DCHO)的合成.用核磁、红外和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、双光子荧光光谱及双光子吸收截面.在800 nm的飞秒脉冲激光激发下,标题化合物发出很强的绿色上转换荧光.化合物2,5-二氰基-1,4-二(4′-甲氧基苯乙烯基)苯的最大吸收波长、单光子发射波长、最大双光子荧光波长、荧光量子产率、双光子吸收系数及双光子吸收截面分别是393 nm、470 nm、475 nm、0.12、0.8 cm/GW、270 GM.这些数据表明,对位甲氧基的D-A-D型化合物具有较好的双光子吸收性能,DCHO是双光子荧光显微与成像应用的一个良好的候选材料.     

含吡啶环双元噁二唑衍生物的合成及其光谱性质和电化学性质

合成了6个含吡啶环的双元噁二唑化合物,产率51%~78%。用1HNMR、FTIR、MS对其结构进行了表征。考察了它们的UV-Vis吸收光谱、荧光光谱,并用循环伏安法测定了其电化学性能。吸收光谱表明:a~c能有效地形成共轭,λmax分别为278、309、282 nm,d~f的共轭效应差,吸收光谱基本相同,λmax分别为273、272 nm和270 nm。荧光光谱表明:目标化合物的DMF溶液发射强的紫色荧光,a和b最大发射波长为398 nm和396 nm,c蓝移到364 nm;d~f出现双发射峰,d和e最大发射峰都在334 nm和345 nm,f红移到342 nm和356 nm,而固体发射强的紫蓝色荧光,在376~414 nm出现最大发射峰;电子亲和势为2.57~3.11 eV,离子势为5.97~6.70eV,说明目标化合物的电子传输性能良好(PBD:EA=2.82 eV)。     

不对称双-1,2,3-三氮唑类化合物的合成及性质研究

以1,1′-联-2-萘酚为原料,经过丙炔化成醚反应和两次Click反应,制备了两个不对称双-1,2,3-三氮唑类化合物A和B,用1H NMR和13C NMR对化合物A和B的结构进行表征,并测试了它们在不同溶剂中的紫外性质和荧光性质。结果表明,两个化合物在不同溶剂中的紫外荧光光谱相似,但紫外吸收强度和荧光强度不同。其中化合物A的最大吸收波长为240～290 nm,其荧光发射光谱在390～440 nm有三个发射峰;化合物B的最大吸收波长为280nm,其荧光发射光谱在370 nm有一个发射峰。     

2,5-二氰基-1,4-二(3'',4'',5''-三甲氧基苯乙烯基)苯的合成和非线性光学性质

报道了具有典型D-A-D型共轭结构的反式2,5-二氰基-1,4-二(3′,4′,5′-三甲氧基苯乙烯基)苯(TMOS)的合成和非线性光学性质.用核磁、红外和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、双光子荧光光谱及双光子吸收截面.在800 nm的飞秒脉冲激光激发下,目标化合物发出很强的黄绿色上转换荧光.TMOS的最大吸收波长、单光子荧光波长、双光子荧光波长、荧光量子产率、双光子吸收系数、最大双光子吸收截面及双光子荧光寿命分别是395 nm、523 nm、526 nm、0.26、1.2 cm·GW-1、405 GM、230 ps.这些数据表明对位甲氧基的D-A-D型化合物具有较好的双光子吸收性能,TMOS是细胞中DNA双光子荧光显微与成像应用的良好候选材料.     

1,8-萘酰亚胺类化合物的荧光光谱性能研究

研究了11种新型1，8-萘二甲酰亚胺类荧光化合物的荧光光谱性能。利用紫外光谱仪和荧光光谱仪测定了这两类化合物的紫外光谱和荧光光谱，分别得到最大吸收波长、最大激发波长、最大荧光发射波长，并以硫酸奎宁的0.5mol／l硫酸水溶液为参比标准，测定了各化合物的荧光量子产率在此基础上，研究了浓度、溶荆对荧光性能的影响、以及化合物结构与荧光性能的关系。结果表明，1，8-萘酰亚胺粪化合物随着浓度的增大，荧光光谱发生红移，且斯托克斯位移增大。随着溶剂极性的增大，最大荧光发射波长发生红移，斯托克斯位移增大，荧光量子产率增大在1，8-萘酰亚胺类化合物的4-位引入笨并呋喃取代基后，最大荧光发射波长红移70nm～100nm，斯托克斯位移增大20nm～50nm，荧光量子产率明显增大。     

4,4′-双(苯并噁唑-2-基)二苯乙烯荧光增白剂(OB-1)的合成

以对甲基苯甲酸及其乙酯为原料,经过三氧化铬在乙酐中的氧化反应、在氯苯溶剂中以氯化亚砜为氯化试剂的侧链氯化反应和亚磷酸三乙酯为乙基化试剂的酯化反应,再经两步缩合反应,合成了荧光增白剂4,4′-双(苯并噁唑-2-基)二苯乙烯(OB-1).OB-1(由Ⅲ合成Ⅳ粗品)的收率由文献中平均90%提高到平均99%以上.通过对化合物的元素分析、红外光谱以及在DMF中紫外吸收光谱的测定,确定了目标产物的结构.经HPLC测定,w(OB-1)＞99%.     

2-取代硫醚-5-[5-(4-氯苯基)吡唑-3-基]-1,3,4-(噁)二唑类化合物的合成及其荧光性质

以5-(4-氯苯基)-3-吡唑甲酰肼为起始原料,经关环和硫醚反应合成了6个新型的标题化合物,其结构经元素分析、IR、1HNMR表征,利用UV以及单光子液体荧光光谱探讨了其光学性质.结果表明,目标产物具有良好的荧光性质,最大发射波长在342 ～ 345 nm之间.     

双波长叠加紫外光度法测定SDBS

研究了硫酸耐尔蓝与十二烷基苯磺酸钠(SDBS)的反应,建立测定SDBS的双波长叠加紫外光度法。在pH=5.02缓冲溶液中,硫酸耐尔蓝与SDBS形成离子缔合物,在紫外区有正、负吸收峰,大正吸收波长位于304 nm,大负吸收波长位于280 nm,摩尔吸光系数分别为ε280为2.5×104L·mol-1·cm-1,ε304为2.2×104L·mol-1·cm-1,当用双波长叠加法时,ε280+304为4.7×104L·mol-1·cm-1,线性范围均为0.5~4 mg/L。研究了反应的适宜条件,用于环境水中SDBS的测定,回收率在98.9%~103.2%。     

Synthesis and two-photon absorption properties of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles

Two symmetrical 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles that exhibit strong two-photon absorption and enhanced two-photon excited fluorescence were designed and synthesized based on “push-core-pull-core-push” molecules built from embedding electron-transporting 1,3,4-oxadiazole in aromatic conjugated system through Wittig–Horner reaction. Pumped by nanosecond laser at 800 nm, strong up-conversion emissions with the central wavelength at 507 nm (green) of 2,5-bis[4-(2-N,N-diphenylaminostyryl)phenyl]-1,3,4-oxadiazole and 475 nm (blue) of 2,5-bis[4-{2-(3-N-ethylcarbazolyl)vinyl}phenyl]-1,3,4-oxadiazole in the solution of CHCl₃ have been observed. Their two-photon absorption cross-sections obtained by nonlinear transmission method are 107 × 10⁻⁴⁸ cm⁴ s photon⁻¹ and 66 × 10⁻⁴⁸ cm⁴ s photon⁻¹. A very effective energy transfer from the excited terminal units to the π-conjugated bridging units of the 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles is the dominant contribution to the two-photon absorption.     

Development of epoxy/rice straw-based cellulose nanowhiskers composite smart coating immobilized with rare-earth doped aluminate: Photoluminescence and anticorrosion properties for sustainability

Novel epoxy resin (E)/CNW nanocomposite coatings were developed with different total contents of rare-earth doped aluminate nanoparticles (REA NPs). The produced epoxy-cellulose nanowhiskers-rare earth doped aluminate nanoparticles (E-CNW-REA) coatings were applied onto mild steel. The epoxy/CNW nanocomposite coatings were characterized by X-ray fluorescence analysis (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDXA), transmission electron microscope (TEM) and infrared spectra (FT-IR). Both colorimetric properties and transparency of the nanocomposite coatings were proved by exploring UV–Vis absorption spectroscopy and CIE Lab parameters. The hardness and superhydrophobic properties were also explored. The photoluminescent transparent coatings showed an excitation at 365 nm, and a bright green emission wavelength at 517 nm under UV light. The corrosion protection performance of the coated mild steel samples soaked in an aqueous solution of sodium chloride (3.5%) was investigated using electrochemical impedance spectroscopy (EIS). The coatings with CNW were found to have anti-corrosion properties. Moreover, the nanocomposite coating with CNW (1 w%) was monitored to exhibit the most pronounced long-persistent photoluminescence for 60 min in the dark. The photoluminescent coatings exhibited highly durable long-lasting phosphorescence. Thus, the current strategy can be considered as a simple promising technology for industrial production of anti-corrosive, superhydrophobic and long-persistent phosphorescent.     

Synthesis,Structural Characterization,Spectroscopic Properties,and Theoretical Investigations of Aminoacridine Derivatives

Synthesis of four N-(heterocyclic)-9-aminoacridine derivatives was investigated. The synthesized compounds, N-thiazolyl-9-aminoacridine (AC1), N-(1,3,4-thiadiazolyl)-9-aminoacridine (AC2), N-(5-methyl-1,3,4-thiadiazolyl)-9-aminoacridine (AC3), and N-(5-phenyl-1,3,4-thiadiazolyl)-9-aminoacridine (AC4) were characterized by FT-IR, ¹H NMR, mass-spectral, and elemental analysis. Amine-imine tautomerism was suggested by density functional theory (DFT) calculations. The optimized structures were obtained using B3LYP/6–311++G(d,p) level of theory. The UV–Vis absorption spectra were measured in various organic solvents. The synthesized compounds AC1–AC4 exhibit absorption spectra characteristic of typical donor–acceptor compounds. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) analysis have been used to explain the internal charge transfer (ICT) phenomena within the molecules. Also, simulated UV spectra were calculated using TD-DFT (B3LYP/6–311++G(d,p) and the results were compared with the experimental values.     

The synthesis,optical properties and x-ray crystal structure of novel 1,3,4-oxadiazole derivatives carrying a thiophene unit

Novel, 1,3,4-oxadiazole derivatives carrying a thiophene unit were synthezised and their structures confirmed by elemental analysis, FT-IR and ¹H NMR. UV–vis absorption and photoluminescence spectroscopy revealed emission peaks located between 427 and 437 nm; the measured absorption λ_max and emission λ_em reflected the electron-donor character of the 1,3,4-oxadiazole derivatives. The crystal structure of one of the compounds was investigated.     

纳米氧化锌的室温合成及表征

文章以醋酸锌、氯化锌和氢氧化钠为原料,在室温下成功制备了氧化锌纳米晶。制备的氧化锌样品用x射线衍射仪、透射电镜、荧光光谱仪等进行表征。XRD结果表明,制备的氧化锌样品为六方纤锌矿结构且具有好的结晶度;从透射电镜照片可以看出,氧化锌颗粒分散性较好,平均粒径在6～10nm;从紫外吸收光谱可以看到,在200-380nm具有很强的紫外吸收,在400-800／lm的可见光区吸收则比较弱;在340nm的激发光下,氧化锌呈现出较好的蓝光和绿光发光效应。     

HPLC separation and wavelength area ratios of more than 50 phenolic acids and flavonoids

Relative retention times and wavelength area ratios for over 50 standard compounds were calculated using reverse-phase HPLC. The standard compounds analyzed included benzoic acids, cinnamic acids, benzene carboxylic acids, acetic acids, coumarins, benzaldehydes and a variety of flavonoid compounds including flavanones, flavones, isoflavones, and their glycosides. Each standard compound was chromatographed by three different gradient elutions. Compounds were detected by UV absorption at 254 nm and 280 nm. Relative retention times with respect to two different internal references and the 254nm: 280nm wavelength area ratio was determined for each standard. Soybean root and seed extracts were analyzed for the presence of the standard compounds using the chromatographic conditions described.     

含受阻胺结构的苯并三唑光稳定性和热稳定性研究

测试了4种2-[2’-羟基-3’-叔丁基-5’-（3-丙酸-4-哌啶酯基）苯基]-2H-苯并三唑结构类光稳定剂紫外吸收光谱、光稳定性及热稳定性。4种化合物在270～400nm均有较强的吸收峰,与引入受阻胺结构前苯并三唑光稳定剂相比．紫外吸收波长和摩尔消光系数不变。4种化合物的光稳定性和热稳定性明显高于引入受阻胺结构前的苯并三唑光稳定剂。光老化12h后,4种化合物仅分解3．2％～6．9％,引入受阻胺结构前苯并三唑则分解35．0％～36．3％。热稳定性测试表明。4种化合物失重1％时的温度为264～272℃．而引入受阻胺结构前苯并三唑失重1％时的温度分别为227℃和235℃。该类化合物分子内同时具有紫外吸收剂和自由基捕获剂两种功能,为高效光稳定剂。     

含噻吩环1,2,4-噁二唑类衍生物的合成及光电性能

以硫代二甘酸和取代苯甲腈为原料,经酯化、环化、酸化等反应合成了2,5-双[3-苯基-1,2,4-噁二唑-5-基]-3,4-二丁氧基噻吩衍生物,通过1HNMR、FTIR和元素分析进行了结构表征,并考察了该系列化合物的紫外-可见吸收光谱、荧光发射光谱及电化学性质。该系列化合物紫外吸收出现在240～250nm和320～350nm两个波段;荧光发射峰位于395～401.5nm,且随苯环上取代基供电子性的增强而规律性红移;循环伏安测定结果表明,该系列化合物中ⅧA、ⅧB、ⅧC和ⅧF具有高于常用电子传输材料2-(4-联苯基)-5-对叔丁基苯基-1,3,4-噁二唑(PBD)的电子亲和势,因而该类化合物的研究,对设计小分子类电致发光材料有重要意义。