In this paper,the SERS(Surface enhanced Raman scattering) method is for the first time employed as a probe to investigate the interaction between the photosensitizer ALPCS and the nucleic acid bases.The advantage of this method is that it can Provide important information on the sensitive slids and damaging process which can't be achieved by other methods.The obtained results suggest that G(Guanine) is most senSitive and vulnerable and the A(Adenine) is less vulnerable,while C(Cytedne) and U(Uracil) are totally not sensitive to the photosensitizer at all. The experiments have confirmed that singlet oxygen, the product of ALPCS photodynamic reaction, pays an importmant role in the damaging process of G and A.

Using a 1.1 W,90 fs commercial regenerated mode locked Ti:Sapphire laser as the pump source,and KTP as the nonlinear gain medium, we construct a synchronously Pumped fs OPO. Its tuning range is 1.04~1.26 μm,the average output power is about 100 mW,and the pulse width is about 100 fs.

The experimental arrangement and a data processing method used to find the real emission spectrum by means of PTGS are proposed.The plasma's radiation temperature is also given.

In this paper,the measurement of the dew point pressure of carbon dioxyde in porous media with a laser testing technique is reported and the experimental results are given.

The principle and the fabricating technology of the monolithic integrated waveguide demultiplexer are discribed in brief.The demultiplexer has been tested with two laser beams(632.8 nm,785.5 nm) traveled in a fiber.In the experiment,the two laser beams of different wavelengths,which are separated at the output end of demultiplexer, are observed successfully.

Based on the models of the integrating photonic"transistor",a model of new things filter-one kind of the application device of the integraing photonic "transistor"is researched and analyzed.

A 30vol.-% TiCp/Ni-alloy composite material was cladded on steel 1045 using a 2 kW laser.The clad layer of the coating presents TiC particles,primary γ-Ni dendrites and the eutectics of γ-Ni+ Cr,Fe)23C6 in the interdendritic regions.Depending mainly on their sizes,TiC particles can not only be trapped by the advancing solid/liquid interface and thus distribute within the γ-Ni dendrites,but also be pushed away by the interface into the interdendritic regions together with the eutectics. The morphology of TiC particles are closely related to their dissolution and precipitation behavior during laser claddin. The growing mechanism of TiC particles are as follows: (1) radiated or stapped lateral growth at the edges of original particles; (2) bridging growth of the particles in cluster; (3) faceted growth of newly independently nucleated TiC particles in the liquid phase and (4) precipitation of TiC γ-Ni extended solid solution.

This paper describes the experimental apParatus of laser shocking,the chemical compositions and mechanical properties of aviation aluminium alloys 7475T761 and 2024T62 and the shapes of laser shocked test pieces.The pull-pull fatigue test data of both laser shocked and unshocked test pieces(or sections) are obtained.The test data show that laser shocking can improve effectively the properties of aviation aluminium alloys against fatigue fracture.

Nanosize powder was formed by using excimer laser ablation of Cu and Al targets under different conditions.The powders were analysed by transmission electron microscopy.The experimental results show that the formed powders were(CuO)6.CuZO and AIN respectively.The size distribution was measured to be closely log-normal with a small geometric standard deviation.

A calculating model of nonideal unstable ring resonators with 90°beam rotation is given in this paper. Influences on the light-field by aberrations of spherical aberration,astigmatism,coma,tilt and inhomogeneity of gain are calculated and analyzed using the Fast Fourier Transform method.

Nd:S-VAP is a new and efficient laser host.The dirge-laser end-pumped lasing of Nd:S-VAP was reported.The single-transversal TEM00 has been obtained.The pumping threshold is 11 mW,and the slope efficiency is 26.7%.

In this paper,a new method to improve the intensity homogeneity of the output beam of an excimer lasers is introduced.Experimental results and a concise analysis are presented.

A theory for single-mode photorefractive oscillator is derived in the weak-field limit so that pump depletion can be neglected.Its intensity and frequency pulling are analyzed for the different nonlocal phase shift.In addition,the linear stability analysis shows that the operation of the oscillator is stable.

A thin film of indium phthalocyanine(InPc) was obtained by vacuum deposition on single-crystal silicon.The ellipsometric spectra of the InPc thin film have been investigated on a scanning ellipsometer with the analyser and polarizer rotating synchronously.It is revealed that there is a comparatively large absorption in the wavelength range of 600~800 nm.The spectrum is explained with its energy levels structure.