Phloxine B (2,4,5,7-tetrabromo-4,5,6,7-tetrachlorofluorescein disodium salt), also referred as D&C red dye no. 28, is phototoxic to many insects such as Tephritidae fruit flies. Sunlight photolysis of phloxine B in aqueous solutions was a first order kinetic reaction at low concentrations. But it turned to be more complex reactions with the increase of phloxine B concentration. The half-lives of phloxine B (6-120 ${\mu}$M) were 18-41 and 52-289 hours in oxygenated and deaerated distilled water, respectively. The photolysis rate constants increased as the phloxine B concentrations increased. The singlet oxygen formation positively correlated with the concentrations of phloxine B and humic acid in oxygenated distilled water. The formation of singlet oxygen did not stop even after the complete degradation of phloxine B, which suggested an involvement of photoproduct-mediated reactions. The results showed that singlet oxygen mediated photooxidation was a dominant reaction for phloxine B dissipation in an aqueous solution, and the self-sensitized and photoproduct-mediated reactions were also involved at the higher concentrations. Iodide and bromide ions significantly decreased phloxine B photolysis rate constants, which were in relation to the decrease of singlet oxygen formation.

The fluorescence quenching of 5-methyl-3-phenyl-2-[s-oxadiazol-2'-thionen5'-yl] indole by carbon tetrachloride ($CCl_4$) and aniline in different solvents viz., dioxane, benzene, toluene, methanol, propanol has been carried out at room temperature to understand the role of quenching mechanisms. The Stern-Volmer plots have been found to be linear. As probability of quenching per encounter 'p' is less than unity, and the activation energy for quenching 'E$_{a}$' is greater than the activation energy of diffusion 'E$_{d}$', it is inferred that the fluorescence of quenching mechanism is not due to material diffusion alone.e.e.

TiO$_2$ has been used as photocatalyst since two and half decades ago. The efficiency in its photocatalytic reactions has been improved by increasing the surface area of the photocatalyst by supporting fine TiO$_2$ particles on some porous materials. In this work, heteropolytungstic acid (HPA) - encapsulated into the titanium exchanged SBA-15 mesoporous materials (TiSBA-15) were prepared and characterized. Also their photocatalytic effects on decomposition of phenol were investigated and the photodecomposition rates of the phenol were observed to be increased by 2.5 8 fold, as compared to those observed in the presence of HPA-encapsulated SBA-15 or TiSBA-15 without HPA.

The tetradecameric peptide (K47-K60) near the NH$_2$-terminal region of epithelial-cell adhesion molecule (Ep-CAM) was chosen as antigenic site and a polyclonal antibody was generated, which could recognize Ep-CAM from the mouse colon tissue or the colon cancer cell, CT-26, in Western blot analysis. Then, the fluorescein isothiocyanate (FITC), a fluorescence dye, was conjugated with the affinity purified Ep-CAM antibody using thiocyanate and the amino groups of FITC and antibody, respectively. The molar ratio of FITC to antibody was estimated approximately 1.86 to 1.00 by measuring the optical densities at 492 nm and 280 nm. Ep-CAM antibody-FITC conjugate was then used for immunohistochemistry of the CT-26 cells. Judging from the shapes formed by fluorescence, the Ep-CAM antibody could delivered FITC to the surface of cells in which Ep-CAM was expressed. This result implies that Ep-CAM antibody could be also used for the tissue-specific delivery of the photosensitizer to the target protein via antigen-antibody interaction.

Photoreactions of some carbonyl compounds with TiO$_2$ were investigated in methanol. Although 1,3-cyclohexanedione and phthalimide afforded 3-methoxy-2-cyclohexen-l-one and 3-methoxy-1-isoindolinone, respectively, acid anhydrides such as succinic, phthalic, and maleic anhydrides gave the monoesters of dicarboxylic acids in good to excellent yields, when they were irradiated on TiO$_2$ in methanol with 300 nm UV light.

The psbA gene of photo system II was cloned and characterized from the P. ginseng chloroplast. The psbA gene is composed of 1,062 nucleotides. The overall amino acid sequence shows 99% and 98% identities to dicots and monocots of higher plants, respectively. Southern blot analysis revealed that a single copy of the psbA gene existed in the chloroplast genome. Northern blot analysis of the in vivo accumulation of the psbA transcript, after being grown under the different intensities (5%, 10%, 20%, and 100%) of daylight, indicated that the steady-state level of the psbA transcript was not significantly affected by light intensity.

The composites fabricated by blending nonlinear optical (NLO) chromophore such as {4-[2-(4-nitrophenyl)-vinyl] phenyl}diphenylamine (NVPDA) with photoconducting crosslinkable matrix, bis-(4-ethynylphenyl)-(4-octyloxy-phenyl)amine (BEOPEA), showed photorefractive property. Many problems faced in typical organic photorefractive systems such as time-consuming chemical synthesis, difficulty in rational design, intrinsic instability and phase separation could be avoided by this fabrication method.

We have systematically studied the evolution of the photoluminescence(PL) tuning of porous silicon(PS) by electrochemical etching in various mixed electrolytes. The electrolytes employed as an etchants were mixtures of HF:CH$_3$COOH:HNO$_3$:C$_2$H$\_$5/OH solutions where the composition ratios (%) were varied from 10:1.98:0:88.02 to 10: 1.98:8.4:79.62 under constant concentration of HF and CH$_3$COOH with a total volume of 100 ml. Changes in the surface morphology of the samples caused by variations in the etching process were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). After samples are etched in various mixed electrolytes, FTIR analyses show that there is the non-photoluminescent state and the photoluminescent state simultaneously. The PL spectra show the PL tuning in the ranging from 560 to 700 nm with the increase of HNO$_3$ concentration. An analysis of the subsequent PL relaxation mechanism was carried out by time-correlated single photon counting (TCSPC) method. Based on experimental results, it is assumed that a red shift of the main PL peak position is related to the HNO$_3$ activated formation of silicon oxygen compounds. Therefore, the use of electrolyte mixtures with composition ratios can be obtained adequate and reproducible results for PL tuning.