Raman spectroscopy technology has a wide range of applications.In this article,Raman spectroscopy is applied into security inspection.With the self-developed Raman security inspection system(Model: RT1003,NUCTECH Co.Ltd.),we detect some flammable and explosive liquids,toxic chemicals,strong oxidizing and strong corrosive liquids,such as gasoline,kerosene,diesel,benzene,toluene,ether,carbon tetrachloride,hydrogen peroxide,sulfuric acid,nitric acid,etc,establish a Raman spectra database of common dangerous liquids.RT1003 Raman security inspection system is now on trial at Beijing South Railway Station,and is well received.

Ti1-xCoxO2 nanoparticles were synthesized by annealing dry gel in the air.The Ti1-xCoxO2 dry gel was produced by the reaction mainly between Tetra-n-butyl Titanate and cobaltous nitrate.The crystal structure and the magnetic properties of the Ti1-xCoxO2 nanoparticles were investigated by thermogravimetry-differential thermal analysis(TG-DTA),X-ray diffraction(XRD) patterns,Raman spectroscopy and vibrating sample magnetometer(VSM).It was found that the Co doped TiO2 nanopartilce is anatase structure when the annealing temperature is 500℃.A phase of CoTiO3 began to appear when the content of Co was higher than 5%.Also,the content of Co element has the effect on the magnetic properties of the samples.When x≤0.050,the magnetic properties increased with the increase of the Co content.When x0.050,a transition from ferromagnetism to paramagnetism could be observed.

Fe-doped TiO2 diluted magnetic semiconductor nanoparticles were prepared by sol-gel method,and were annealed in air under different temperatures.The crystal structure and the phase transition temperature of the nanoparticles were analyzed by thermogravimetry-differential thermal analysis(TG-DTA) and X-ray diffraction(XRD) patterns.It is found that anatase structure exists under lower annealing temperature.A small quantity of rutile phase appears when the temperature was 600℃,and rutile has become the dominant component when the annealing temperature reaches 700℃.The magnetic properties of the nanoparticles were measured by vibrating sample magnetometer(VSM).Room temperature ferromagnetic Ti0.95Fe0.05O2 nanoparticles were successfully obtained after annealed at 450℃,500℃,700℃.

Co-doped TiO2 diluted magnetic semiconductor nanoparticles were prepared by sol-gel method,and were annealed in air under different temperatures.The crystal structure and the phase transition temperature of the nanoparticles were analyzed by thermogravimetry-differential thermal analysis(TG-DTA),X-ray diffraction(XRD) patterns,Raman spectroscopy and transmission electron microscope(TEM).The magnetic properties of the nanoparticles were measured by vibrating sample magnetometer(VSM).It is found that anatase structure exists under lower annealing temperature.A small quantity of rutile phase appears when the temperature was up to 823 K,and rutile has become the dominant component when the annealing temperature reaches to 873 K with a little amount of CoTiO3.The magnetic properties of the samples are also seriously influenced by the annealing temperature.A transition from paramagnetism to ferromagnetism is observed in room temperature M-H curves with the increase of annealing temperature.Room temperature ferromagnetic Ti0.975Co0.025O2 nanoparticles were successfully obtained after annealed at 873 K.