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The nano-Ag films were prepared by RF magnetron sputtering technique, and all of them were treated by rapid thermal annealing at different temperatures. The structure, the morphology and the optical properties of the annealed nano-Ag films were characterized by X-ray diffraction, scanning electron microscopy, and UV-Vis-NIR spectroscopy. The experimental results show that the open area fraction of the film and spacing between islands or nanoparticles increase with the increase of the annealing temperature, while the aspect ratio decreases. The anisotropic worm-like island films have been reshaped into isotropic nanospheres. The surface plasmon (SP) resonance band blue shifts and narrows continuously with increasing heating temperature. Analyses show that the SP resonance of the nano-Ag films can be modulated by morphology evolution induced by rapid thermal annealing.

The fluorescence characteristic of various free radical photoinitiators was investigated by fluorescence spectroscopy. The influence of conjugated structure on fluorescence spectrum was analyzed from the molecular structure. The results show that: the wave length of fluorescence excitation spectrum gradually augments with the conjugative effect enhancement, and so does the peak of fluorescence emission spectrum. The transient fluorescence spectrum of photoinitiator is affected by electron groups and the fluorescence decay of photoinitiators with electron-withdrawing groups is faster than that of photoinitiators with electron-donating groups. The excitation peak of photoinitiator has evident red shift with the polarity of solvent increasing, which shows that transition type is pi-pi* transition, and the fluorescence decay is postponed with the solvent glutinosity changing. When the photoinitiator density is at 10(-2) mol x L(-1), the fluorescence decay is evidently fast because of quenching effect caused by self-absorption and collisions between particles.

In the present paper, the J-aggregate structures of three types of cyanine dyes adsorbed both on 0.4 microm AgBrI cubic crystal surface (100) and on 1.8 microm AgBrI tabular crystal surface (111) were studied by use of atomic force microscope (deltaFM). Several types of aggregation structures were observed for the three types of dyes on AgBrI crystals. Rectangular structure was formed on the crystal faces of (100) and (111) for both anionic and cationic cyanine dyes. On the surface of anionic-cationic cyanine dyes, however, herringbone stacking structure was formed, and a banded spectrum was correspondingly detected on the AgBrI crystal surface.

The J-aggregates and the photosensitive properties of two kinds of mixed cyanine dye and the corresponding independent cyanine dyes absorbed on AgBr cubic microcrystal were investigated. The reflection spectra of the J-aggregates of the mixed cyanine dyes and the corresponding independent cyanine dyes were measured by the use of UV-Vis spectroscopy. The results showed that the absorption band of the mixed J-aggregates absorbed on AgBr cubic microcrystal had two-peak wavelengths and accorded with the independent cyanine dyes, respectively. The sensitive performance of the mixed cyanine dyes was much enhanced compared to the corresponding cyanine dyes.

In the present paper, the fluorescence spectral curves of J-aggregates of two kinds of anionic-cationic cyanine dyes adsorbed on AgIBr cubic microcrystals were measured by using fluorescence spectroscopy, and compared with the sensitivity characteristic of anionic-cationic cyanine dyes. The results show that the peaks of fluorescence spectral curves of anionic-cationic cyanine dyes were lower than that of anionic and cationic cyanine dyes, and the higher sensitivity efficiency was due to the fact that more electrons transfer to the surface of AgIBr microcrystal.

The temporal behaviors of free photoelectrons and shallow-trapped electrons were measured in the cubic AgCl emulsion with the microwave absorption and dielectric spectrum detection technique. The results indicate that the chemical sensitization makes the photoelectron decay slower than that of the unsensitized AgCl emulsion, and the decay time is prolonged in the sulfur-plus-gold sensitized emulsion, because the shallow electron trap effect of sulfur-plus-gold sensitization center restrains the recombination of photoelectron and hole. The photoelectron decay is pricked up and the decay time is shorter in sensitized emulsion than that in the unsensitized AgCl emulsion, because the J-aggregates increase the interstice silver ion density in the AgCl microcrystal and accelerate the recombination of interstice silver ions and electrons. The decay time of photoelectron in chemistry-and-spectra sensitized emulsion is also prolonged, and the shallow electron trap effect of chemical sensitization center is more distinct under the condition of spectra sensitization.

The silver chloride microcrystals emulsion which are sensitized by the adsorbed green-sensitive cyanine dye of different concentration, was studied by using the absorption spectrum. The experiments show that when the sensitizing concentration is less than 0.02 mL (5.0 mg x mL(-1))/40 g emulsion, the dye J-aggregate is not formed on the surface of silver chloride microcrystals; when the dye concentration is more than 0.2 mL (5.0 mg x mL(-1)/40 g emulsion, the dye J-aggregate is formed on the surface of silver chloride microcrystals; compare to the M-state of dye, the maximal absorption peak of J-aggregate shifted to a longer wavelength by about 50 nm. It was found, when the J-aggregate is formed, the absorption in the wavelength range of more than 450 nm is increased.

The photoelectron decay characteristic directly reflects the photographic efficiency of silver halide crystals. Measurement of the electronic decay time-resolved spectrum of silver halide microcrystals can provide important information about the photoelectron decay action in latent image formation process. In order to know the influence of shallow electron trap dopant K4 Fe (CN)6 and S+Au on photoelectron decay, the photoelectron decay time-resolved spectra of AgCl emulsion doped by K4 Fe(CN) and that doped by K4 Fe(CN) firstly and then sensitized by S+Au were detected by microwave absorption dielectric technique, which can be used to study the decay process of free photoelectrons and shallow-trapped electrons in semiconductor crystals. The experimental results show that when the doping content is 10(-8)-10(-7) mol x mol(-1) Ag, the photoelectron decay process becomes slower, namely, the photoelectron decay time is longer, as the doping is near the grain surface before sensitization. After S+Au sensitization, the photoelectron decay becomes faster, showing that the sensitization centre acts as a deep electron trap. And when the doping is near the grain surface with 90% Ag, the photoelectron decay time becomes shorter, showing that the doping centre and the sensitization centre may interact.

The time-resolved spectra of free photoelectrons and shallow-trapped electrons in the T-grains AgBrI emulsion were simultaneously detected with microwave absorption and dielectric spectrum detection technique. The results indicate that the electron trap effects of sulfur sensitization centers and sulfur-plus-gold sensitization centers are different with equal quantities of Na2S2O3 added. The sulfur sensitization centers acted as a deep electron trap to pick up the electronic decay because of increasing the number of deep trapped electrons, while the sulfur-plus-gold sensitization centers as a shallow electron trap decrease the electronic decay through effectively controlling the recombination between the electrons and the holes. The depth of sulfur-plus-gold sensitization center is shallower than that of sulfur sensitization center after the KAuCl4 is added. The effects of sulfur sensitization center and sulfur-plus-gold sensitization center on the photoelectron decay are different in different sections of decay curves through the change in electron time-resolved spectra.

DC glow discharge was used to study N2 molecule at low pressure (4 Torr). The emission spectrum was examined in the range of 320-470 nm in the discharge plasma of N2, which showed that the emission was composed of a series of spectral lines equidistant, and the relative emission intensity became weaker with longer wavelength, whose distribution accorded with Frank-Condon rule. It is attributed to the transition of C 3pi(u)--B3pi(g). On this base, the authors have calculated the vibrational frequency of B 3pig state to be 1738.50 cm(-1). The Frank-Condon factor about C3pi(u) (v' = 0)--B3H(g) (v" = 0-5) was calculated, which is consistent with the results of experiment.

The powder solid state FT-Raman spectra of four unsymmetric dithiolate complexes with formulas (Me4N)2 [M(Ln) (SPh)2] (M=Cd and Zn, L1 = dmit = 1,3-dithiole-2-thione-4,5-dithiolate, L2 = dmid = 1,3-dithiole-2-one-4,5-dithiolate, SPh = thiophenolate) (2-5) and [Bu4 N]2 [Zn(dmit) 2] (1) were studied and characterized by changing the structures of ligands or the metals of the complexes. The blue shift of the C==C peak around 1420 cm(-1) is about 38 cm(-1) when the dmit2- is replaced by dmifd2- . When Zn2+ is replaced by Cd2+ , or dmit2- is replaced by dmid2- , the 990 cm(-1) peaks of the pentacyclic ring shift to red by about 11 and 7 cm(-1) respectively. Two peaks at 463 and 300 cm(-1) were assigned to stretching vibration and bending vibration respectively for the S--C--S bond of S2 C==CS2 in dmit2- or dmid2- . Red shifts of those two peaks are found when dmit2- is replaced by SPh- , or Zn2+ is replaced by Cd2+ ; but they will shift to blue when dmit2- is replaced by dmid2- . There are two peaks of Cd-S vibrations with the sulfur atom from thiophenolate and from the ligands dmit2- or dmid2- , which are at about 180 and 140 cm(-1) respectively. Just like Cd-S, the vibration of Zn--S has two peaks as well, which are at about 193 and 155 cm(-1), respectively.

Spectral sensitivity is a key technology of modern photography. Because J-aggregates of cyanine dye exhibit sharp absorption bands (i.e., J-band), they are important sensitizers. In this article, the J-aggregation behavior of two kinds of anionic-cationic cyanine dyes adsorbed on the AgBrI cubic microcrystals was studied. The reflectance spectral curves of J-aggregating dyes were measured by UV-Vis. spectrophotometer, and were compared with the J-aggregation of anionic and cationic cyanine dyes. The results show that the reflectance spectra of J-aggregates of anionic-cationic cyanine dyes adsorbed on AgBrI microcrystals have peak wavelengths of anionic and cationic cyanine dyes. Anionic-cationic cyanine dyes have two sensitivity regions, including both the sensitivity region of anionic cyanine dye and the sensitivity region of cationic cyanine dye.

The non-resonance Raman spectra of hemin were studied with the excitation of a 632.8 nm laser. The results indicated that the spectra of oxidized and reduced hemin are dominated by B1g vibration modes. The SERS spectral feature demonstrates that the porphyrin plane is perpendicular to the electrode surface. Moreover, the enhancement of the bands related to propionic acid substituents indicates that hemin is attached to the electrode surface via propionic acid substituents. The dependence of the SERS spectra on the electrode potential was examined. One of the B1g modes, nu 15, was found to be highly sensitive to the oxidation state of the central iron in heme group, and thereby exclusively assigned to be the oxidation state marker band for heme iron.

Five different-structure carboncyanine dyes containing fluorine in methanol solution and the aggregate behavior on the surface of AgIBr tabulate grains were investigated, the photographic capability determined and the sensitive multiple calculated. From the monomolecular absorption curves of dye1, dye2 and dye3 in methanol solution, it can be seen that when the substitute changed from C2H5 to CH3 to no substitute, the maximal absorption peak shifted to a shorter wavelength. Sensitive dye with ethylene (dyel) adsorbed on the AgBrI surface formed a higher peak of J-aggregate with a higher sensitive multiple. Sensitive dye with no substitute (dye3) did not form J-aggregate, which had a low sensitive multiple and reduced the sensitivity. Compared with dye5, dye4 had a sharper and narrower reflective spectrum and a higher sensitive multiple. The results showed that a different-structure dye adsorbed on silver halide grains formed a different J-aggregate. The sensitive dye of J-aggregate with a sharper absorption spectrum had a higher sensitive multiple.

Plasma diagnostics is performed during dc. glow discharge plasma-enhanced chemical vapor deposition (PECVD) on nitride thin films using optical emission spectra. Several molecular bands such as the second positive series of N2 transitions, the first negative series of N2+ and the CN, NH violet bands are identified. Variations of the emission intensities of N2(337.1 nm), N2+(391.4 nm) and CN(388.3 nm) are investigated as the function of the percentage of H2, discharge current and deposition pressure. The related excitation mechanism of the species emission is discussed. Experimental results show that adding a small amount of H2(about 5%) into the gas source will be beneficial to produce all the active species. Higher discharge current will result in an increase of the active species concentration while there is maximum emission intensity at medium gas pressure at about 4 kPa. The collisions between the species, including metastable nitrogen and hydrogen are related with the concentration variations of the measured species. All the results and discussion provide reference data for optimizing the deposition parameters and controlling the deposition process in the synthesis of carbon nitride thin films.