五甲氧基红的吸收光谱和皮秒激光光谱研究

进行了五甲氧基红(2、4、2′、4′、2″—五甲氧基三苯甲醇)吸收光谱和皮秒激光荧光光谱研究。发现在酸性低粘度醇类溶剂中,五甲氧基三苯甲基正离子的褪色现象。对其褪色机理及溶剂粘度对于五甲氧基红皮秒激光光谱的影响进行了讨论。     

血卟啉衍生物分子的激光喇曼光谱

本文报道了用激光喇曼散射法测定三种血卟啉衍生物(HpD)样品的喇曼光谱.它们大多处在570～1640cm~(-1)之间.疗效不同的HpD的喇曼谱线位置有一定的差异,反映了卟啉环可能连接有不同的侧链;同一种HpD在不同溶剂中的谱线位置及强度不同,说明不同溶剂分子与样品分子有不同的作用.     

一种高效有机光子选通材料的频域存储功能和机制探讨

报道一种高效光子选通光谱烧孔材料四苯并卟啉锌／巴豆酸／苯氧树脂（ＺｎＴＢＰ／ＣＡ／ＰｈＲ）薄膜的频域光存储性能和机制的研究结果。     

同轴泵浦染料光纤激光器

我们在研究液芯Raman光纤激光器的基础上,研究了一种轴向泵浦的染料液芯光纤激光器。 为了能形成液芯光纤波导,首先要寻找一种折射率较大的染料溶剂,例如采用了苯与甲苯。无疑苯与甲苯是很好的溶剂,其折射率也均大于液芯光纤包层材料石英的折射率(n=1.46)。然而其荧光量子产率很低,大部分激活染料分子被溶剂猝灭。最后我们采用了一种透明无色溶液苯甲醇作为溶剂,其折射率为1.539。用苯甲醇-若丹明6G溶液在普通染料激光器上进行了试验,结果表明它比相同浓度的乙醇-若丹明6G溶液的荧光效率低一些,但能形成激光振荡,说明这种溶剂可以采用。另外,苯甲醇溶液中若丹明6G的荧光峰值比乙醇溶液中发生了一点红移。     

溶剂对激光染料DCM的荧光衰变过程的影响

采用时间相关单光子计数技术测量了激光染料DCM在17种质子化和非质子化溶剂中的荧光衰变时间常数。所观察到的溶剂效应可被认为主要是由于激发态分子构型改变和氢键络合物生成所引起。并据此预言:选用高极性、但不能参与生成氢键的非质子化溶剂,是改善DCM染料激光体系输出特性的有效措施之一。     

自体荧光和肿瘤的光谱诊断研究进展

组织的自体荧光可用于肿瘤的光谱诊断.用不同波长的激光激发组织获得不同的自体荧光光谱特征.它们分别起源于蛋白质(色氨酸)、卟啉-蛋白的能量转移、以及内源卟啉的荧光等.通过促进卟啉的生物合成,可以增强自体荧光;采用时间门光谱技术,可以提高自体荧光诊断的灵敏度.光诱导的荧光变化的探测可以提供光动力产生的单态氧和以卟啉为基础的光动力治疗效率的信息.     

气体的激光光声光谱及其应用

我们建立起一个用光栅调谐的、CO_2激光器作光源的激光光声光谱装置.在C0_2发射波长范围内测定了乙烯、丁二烯、三氯乙烯、苯、氨、甲醇和偏二甲肼等气体的吸收谱图.     

meso-四(对十六烷氧基苯基)卟啉的非线性吸收研究

从理论和实验两方面对新型卟啉化合物5,10,15,20-四(对十六烷氧基苯基)卟啉的非线性吸收特性进行了研究.实验采用开孔Z-扫描方法,使用可调谐纳秒光参量振荡器(OPO)作为光源,获得了710～820 nm波长范围内的Z-扫描曲线.研究表明,该卟啉化合物在较宽的光谱范围内具有大的非线性吸收系数,是一种具有潜在应用价值的新型光限幅材料.     

苯并噁嗪的无溶剂法合成及表征

采用无溶剂二步法制得了双酚A型苯并噁嗪，用红外光谱和核磁氢谱对它进行了表征，并将它的初级产品和溶剂法制得的苯并噁嗪的初级产品的成环率进行了比较。     

溶剂效应对红外光谱影响的研究进展

溶剂效应诱导红外光谱的变化已经广泛应用于溶质-溶剂相互作用的光谱研究.介绍了红外光谱的溶剂效应,并归纳总结了近些年来国内外溶剂效应对红外光谱影响的理论计算和实验的研究进展,为进一步开展红外光谱溶剂效应的研究提供了参考意见.     

The Effect of Core Delocalization on Intermolecular Interactions in Conjugated Dendrimers

Four generations of conjugated dendrimers that contain 1,3,5‐tris(distyrylbenzenyl)benzene cores, stilbene dendrons, and t‐butyl surface groups have been synthesized. The dendrimers were synthesized by coupling benzylphosphonate‐focused dendrons with 1,3,5‐tris(4‐formylstilbenyl)benzene to give the dendrimers in yields in the range 60–82 %. We have probed the optoelectronic properties of the dendrimers by electrochemistry, photoluminescence, and in light‐emitting device structures. We have found that the degree of aggregation is strongly generation dependent. We compared the properties of these benzene‐centered dendrimers with an equivalent family of dendrimers that differs only in having a nitrogen atom as the central unit. We found that the aggregation of dendrimers was strongly dependent on the degree of delocalization across the central unit. The dendrimers with the benzene central unit, which have three localized distyrylbenzene chromophores, were found to aggregate more strongly in the solid state than those with nitrogen as the central unit. In the latter case the electroactive component is comprised of all three distyrylbenzene units and the nitrogen atom.     

Observing the Stimulated Raman Gain Spectra of Solutions Using an Infrared Pump Pulse with Narrow Linewidth and a Low-Noise CW Probe Laser

Stimulated Raman gain (SRG) spectroscopy using infrared pump pulses with narrow linewidth and a low-noise cw probe infrared laser was proposed. High-resolution Raman spectra of solutions were obtained. The SRG spectra of crystal GaP, benzene, and toluene were measured to confirm the spectral resolution and sensitivity over the terahertz (THz) region. We discuss the polarization dependence of the spectral measurement of carbon tetrachloride. Our system can detect organic molecules in aqueous solutions.     

Prospects of a slotline utilization as the excitation element of a quasi-optical hemispherical resonator for the problems of liquids dielectrometry

Inthis article we propose the utilization of a quasi-optical resonator in the form of the resonant cavity of hemispherical shape in the metal as a measurement cell of a dielectrometer for the investigation of electrophysical properties of liquids. We have carried out the investigations of electromagnetic characteristics of the utilized resonator in the case of the air filling and of the partial filling by the analyzed liquids (benzene, butanol, ethanol, methanol). The possibility of effective excitation of whispering gallery modes using the slot line has been demonstrated. We have determined the possibilities of the utilized investigation technique of the electrophysical properties of different liquids and of their identification based on the variations of electromagnetic characteristics of the proposed measurement cell. It has been shown that in the case of a small perturbation of the resonance fields by samples of liquids (with volume up to 3 ml) this technique for the proposed resonator possesses a high sensitivity and resolution capability for the identification of liquids with a relatively small difference of the electrophysical parameters.     

Tumor localization and photosensitization by derivatives of hematoporphyrin: A review

A mixture of porphyrins derived from hematoporphyrin and termed HPD (hematoporphyrin derivative) has been useful for localization and therapy of neoplastic disease. The fluorescence and photosensitization of tissues which accumulate an HPD fraction have been examined by many research groups, and the clinical applications of these phenomena are now being explored.     

准分子激光泵浦的可调谐染料激光的研究

用KrF准分子激光泵浦PTP染料,在甲醇、乙醇、环已烷和二(口恶)烷四种溶剂中得到了紫外激光,调谐范围为335.8～345.9毫微米,激光线宽约8埃。用乙醇作溶剂时激光转换效率为21％。     

Characteristics of a Raman laser excited by an ordinary ruby laser

The stimulated Raman effect of benzene has been observed using an ordinary (nongiant) ruby laser. The build-up of oscillation at the v2, 2v2, 3v2and 4v2Stokes lines and also at the first v1Stokes line have been observed. The threshold exciting power for laser action in the v2Stokes line has been measured to be 9.5 kW. A rate equation for the Raman laser has been given, and the total scattering cross section for the v2Raman line of benzene has been determined as σ = 0.46×10^-28cm². The estimation based on the results of this investigation indicates that it is possible to construct a Raman laser of benzene using an Ar gas laser.     

Spectral hole burning in dye solutions

Using picopulses generated by a mode-locked ruby laser, we have measured the 3-8-Å bandwidth of a hole burned in the 0-0 transition of cryptocyanine in methanol and demonstrated the inhomogeneous chatacter of this transition. The population-rate equations are written for an inhomogeneous transition with two and four energy levels interacting with continuous or pulsed excitation. Using the numerical solutions of this model together with the experimental result we determine a transverse relaxation timeT_{2} = 0.6-1ps for cryptocyanine in methanol.     

Miniaturized Electronic Nose System Based on a Personal Digital Assistant

A small electronic nose (E‐Nose) system has been developed using an 8‐channel vapor detection array and personal digital assistant (PDA). The sensor array chip, integrated on a single microheater‐embedded polyimide substrate, was made of carbon black‐polymer composites with different kinds of polymers and plasticizers. We have successfully classified various volatile organic compounds such as methanol, ethanol, i‐propanol, benzene, toluene, n‐hexane, n‐heptane, and c‐hexane with the aid of the sensor array chip, and have evaluated the resolution factors among them, quantitatively. To achieve a PDA‐based E‐Nose system, we have also elaborated small sensor‐interrogating circuits, simple vapor delivery components, and data acquisition and processing programs. As preliminary results show, the miniaturized E‐Nose system has demonstrated the identification of essential oils extracted from mint, lavender, and eucalyptus plants.     

Laser induced fluorescence spectroscopy from native cancerous and normal tissue

The visible fluorescence spectra have been measured from cancerous and normal rat kidney and prostate tissues, and from cancerous rat and mouse bladder tissues. The spectral profiles from the cancerous and normal tissues are substantially different; showing characteristic principal and secondary maxima. These peaks are assigned to fluorphors such as flavins and porphyrins in different environments in the two types of cell media.     

Treatment of the surface of blanks for fabrication of CdZnTe-based detectors

The depth of the damaged layer forming on the surface of the CdZnTe crystals during standard mechanical treatment of them is determined by the microhardness measurement and chemical selective etching. The rates of chemical etching of the surface of the CdZnTe crystals in the solutions of bromine in methanol with various bromine concentrations are determined.