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The content control of the impurities in refined TiCl₄ becomes the key part for the quality control of titanium material. Refined TiCl₄ is the key procedure in producing titanium sponge. Besides, the content of the impurities in titanium sponge and that of the impurities in refined TiCl₄ presents the 4-times enrichment relationship. Therefore, control the content of the oxygen, there is the need to analyze the source of oxygen impurities so that strict control can be conducted over the impurities of refined TiCl₄. Determination of TiOCl₂ in refined TiCl₄ was significant for analysis of its impurities. TiOCl₂ could be determined by infrared spectroscopy due to its infrared characteristic spectrum line. However, normal infrared absorption cell was not fit for the sample analysis, because TiCl₄ easily reacted with moisture in the air and immediately was hydrolyzed to form highly corrosive hydrochloric acid smoke. According to Lambert-Beer Law, which means the concentration (c(x)) and absorbance (A)-length (L) curve's slope have direct ratio. The infrared absorption cell with the window film of ZnSe (Φ10 x 1 mm, wavenumers: 7800-440 cm⁻¹) and the glass cell (optical path: 22, 12, 7 and 4 mm) was assembled and utilized in determination of the TiOCl₂ in refined TiCl₄ by standard addition method. The detection limit of TiOCl₂ was 17.8 mg · kg⁻¹, the regression equation was Y = 1.011 8X, R = 0.9963; With standard addition method, the regression equation of TiOCl₂ was Y = 1.940 0X, R = 0.997 0, it' s good in linearity relation, the TiOCl₂ content in refined TiCl₄ is determined to be 833.8 mg · kg⁻¹ and SD up to 40.0 mg · kg⁻¹. RSD of the method precision is between 0.95%-1.94%, while recovery rate is between 88.5%-93.1%. This infrared absorption device was safe, simple and convenient, easily removable and washable, and re-useable. The method could conduct the quantitative analysis over the TiOCl₂ content in refined TiCl₄ through adding standard sample for one time, it could meet the requirement of determination of TiOCl₂ in refined TiCl₄.

Refined TiCl4 is the key procedure in producing titanium sponge. Besides, the content of carbon and oxygen (C and O) impurities in titanium sponge and that of C and O impurities in refined TiCl4 presents the 4-times enrichment relationship. Therefore, the content control of the C and O impurities in refined TiCl4 becomes the key part for the quality control of titanium material. In order to control the oxygen and carbon, there is the need to analyze the source of C and O impurities so that strict control can be conducted over the impurities of refined TiCl4. Determination of CO2 in refined TiCl4 was significant for analysis of its impurities. CO2 could be determined by infrared spectroscopy due to its infrared characteristic spectrum line. However, normal infrared absorption cell was not fit for the sample analysis, because TiCl4 easily reacted with moisture in the air and immediately was hydrolyzed to form highly corrosive hydrochloric acid smoke. According to Lambert-Beer Law, which means the concentration (c(ξ)) and absorbance(A) - length (L) curve's slope have direct ratio. The infrared absorption cell with the window film of ZnSe (φ10 mm x 1 mm, wavenumers: 7 800 -440 cm(-1)) and the glass cell (optical path: 42, 22, 12, 7 and 4 mm) was assembled and utilized in determination of the CO2 in refined TiCl4 by standard addition method. The detection limit of CO2 was 0.92 mg x kg(-1), the regression equation was Y = 0.031 1X, R = 0.997 2; With standard addition method, the regression equation of CO2 was Y = 0.131 7X, R = 0.998 6, it's good in linearity relation, the CO2 content in refined TiCl4 is determined to be 1.53 mg x kg(-1) and SD up to 0.04 x mg x kg(-1). RSD of the method precision is between 0.53%-1.27%, while recovery rate is between 89.2%-96.8%. This infrared absorption device was safe, simple and convenient, easily removable and washable, and re-useable. The method could conduct the quantitative analysis over the CO2 content in refined TiCl4 through adding standard sample for one time, it could meet the requirement of determination of CO2 in refined TiCl4.

Near-infrared hypserspectral imaging technology was applied for the discrimination of a variety of life states, the judgment of being alive or death. Discrimination models were built based on spectral data of Pieris rapaes acquired during different life states. The wavelengths from 951.5 to 1649.2 nm were used for analysis after the removal of spectral region with obvious noises at the beginning and the end. And the spectra data of 951.5-1649.2 nm were preprocessed by different pretreatment methods. To discriminate the state of being alive or death of Pieris rapaes, discrimination models were built based on the spectral data processed by different pretreatment methods. Results showed that the discriminant accuracy can approach or attain 100%. Thus the method was proved to be useful for the discrimination of the state of being alive or death of Pieris rapaes. After the spectral data were preprocessed by moving average (MA) algorithm, 17 characteristic wavelengths were extracted based on weighted regression coefficient (Bw) and 20 were extracted based on successive projections algorithm (SPA) to identify the state of being alive or death of Pieris rapaes. Four classification methods based on characteristic wavelengths, including partial least squares-discriminant analysis (PLS-DA), K-nearest neighbor algorithm (KNN), back propagation neural network (BPNN) and support vector machine (SVM) were used to build discriminant models for identifying the state of being alive or death of Pieris rapaes. The discriminant accuracy all can approach or attain 100%.

Nanocrystalline ZnO films were deposited on quartz substrates by radio-frequency magnetron sputtering (RFMS) method. The authors discussed the effect caused by the change in the ratio of oxygen to argon and quartz substrates temperature on the qualities of thin films and blue photoluminescence spectrum of ZnO films. Relationship between XRD intensity and FWHM of nanocrystalline ZnO films at different ratio of O2/Ar in processing was given. Photoluminescence spectrum (PL), absorption spectra (ABS), photoluminescence excitation spectrum (PLE) and X-ray diffraction pattern (XRD) of nanocrystalline ZnO film with excitation wavelength 300 nm were measured at room temperature. XRD pattern indicates that nanocrystalline ZnO film has a hexagonal wurtzite structure and is polycrystalline. Blue visible emission bands (430-460 nm) were observed, and its central wavelength is 445 nm. The relationship between PL area of integration and PL intensity of maximum of nanocrystalline ZnO films at different ratio of O2/Ar in processing was given. The luminescence emission peak located at 450 nm corresponds to the transition from the shallow level of oxygen vacancy to valence band or the interstitial.

It is known that zinc oxide is a kind of important functional and novel material of II-VI wide bandgap semiconductor (Eg = 3.37 eV), and has excellent microstructural, chemical and physical properties. The intensity of photoluminescence, luminescence peak positions and other kinds of luminescence properties of ZnO : RE3+ nanocrystalline are strongly dependent on the annealing temperature and time, and the concentration of the doping rare earth ions. Terbium-doped zinc oxide nanocrystalline were successfully prepared by sol-gel process at different annealing temperature. Photoluminescence spectrum (PL), photoluminescence spectrum excitation(PLE) and X-ray diffraction pattern(XRD) of nanocrystalline ZnO : Tb3+ with excitation wavelength 368 nm were measured at room temperature. The emission from 5D4-->7F6 (485 nm), 5D4-->7F5 (544 nm), 5D4-->7F4 (584 nm) and 5D4-->7F3 (620 nm) of Tb3+ ions, and the wide visible band of ZnO were observed. Photoluminescence intensity of nanocrystalline ZnO : Tb3+ on the doping concentration and annealing temperature was given, and it was found that the optimal dopant concentration and annealing temperature were 4 at% and 600 degrees C, respectively. The luminescence process of Tb3+-doped zinc oxide nanocrystalline was investigated by using PL and XRD. The photoluminescence mechanism suggests that there is energy transfer between ZnO nanocrystalline hosts and the doping Tb3+ centers.

Europium-doped zinc oxide nanocrystalline was successfully prepared by sol-gel process. Photoluminescence spectrum (PL), Photoluminescence excitation spectrum(PLE), and X-ray diffraction pattern(XRD) of nanocrystalline ZnO : Eu3+ with excitation wavelength 395 nm were measured at room temperature. The XRD pattern indicates that nanocrystalline ZnO : Eu3+ has a hexagonal wurtzite structure and is polycrystalline. The mean grain size of nanocrystalline ZnO : Eu3+ was calculated by Debye-Scherrer formula. The luminescence process of Eu(3+) -doped zinc oxide nanocrystalline was investigate using PL and PLE. Emission of 5D0 --> 7F1 (595 nm), 5D0 --> 7F3 (653 nm), 5D0 --> 7F2 (611 nm) of Eu3+ ions, and a weak and wide visible band of ZnO were observed. Also, the photoluminescence of nanocrystalline ZnO : Eu3+ exhibits a blue-shift. An energy transfer from excited states of ZnO hosts to doped Eu3+ ions centers was disclosed by the fact that that photoluminescence intensity maximum of nanocrystalline ZnO : Eu3+ changs with the doping concentration of Eu3+.

Er3+ -doped zinc oxide nanocrystalline powders were successfully prepared by chemical precipitation method. Photoluminescence spectrum (PL), photoluminescence spectrum excitation(PLE) and X-ray diffraction pattern (XRD) of the nanocrystalline ZnO:Er3+ with excitation wavelength 365 nm were measured at room temperature. XRD pattern indicates nanocrystalline ZnO:Er3+ has a hexagonal wurtzite structure and polycrystallining. The mean grain size of nanocrystalline ZnO:Er3+ was calculated with Debye-Scherrer formula. The luminescence process of Er3+ -doped zinc oxide nanocrystalline was investigated by using PL and PLE. Emissions of S(3/2)(550 nm), 2H(11/2))(521 nm) and 4F(5/2)(456 nm) of Er3+ ions were observed in wide visible band of ZnO. By analyzing the spectrum the effect of Er3+ -doping on the luminescence of ZnO was studied. An energy transfer from excited states of ZnO hosts to doping Er3+ ions centers was disclosed by the fact that photoluminescence intensity maximum of nanocrystalline ZnO = Er3+ changed with the doping concentration of Er3+.

A new catalytic spectrophotometric method for the determination of trace amount of Mn(II) was developed. The method is based on the oxidation of 7-(2-nitryl-4-methyl phenylazo)-8-hydroxy-qinolin-5-slfonic acid by potassium periodate in the presence of nitrilo triacec acid as an activator and CTMAB as a sensitizer. The wavelengths for the determination was 509 nm. The linear range of determination is 0-3. 2 x 10(-9) g x mL(-1) for Mn(II). The determination limit is 3.8 x 10(-11) g x mL(-1). The interference of foreign ions was studied. The method can be used for the determination of Mn(II) in mung bean, rice, cereal and soil samples.

The effects of acidity and temperature on the fluorescent characteristics of N-N-bis-(O-Carboxylphenyl)-Oxamide (OBBE) have been studied in details. And the quantum efficiency of fluorescence has been measured. In a pH 8-9.5 buffer medium of H3BO3-NaOH, OBBE has a maximum excitation wavelength at 210 nm and a maximum emission wavelength at 395 nm. The nitrate reacts with OBBE and quenches the fluorescent intensity of OBBE. Thus a new sensitive method using the quenching of synchronous fluorimetry has been developed for the direct determination of nitrate in water. The linear calibration curve was obtained in the range of 0.0028 and 0.16 mg.L-1, the detection limit was 0.0028 mg.L-1. The proposed method has been applied to the determination of nitrate in water with satisfactory results.

The plasma was acquired with a pulsed Nd:YAG laser beam ablating aluminum. The pulse energy was set up to 145 mJ per pulse. Ar was used as surrounding gas with the pressure of 100 kPa. The radiation of the plasma was recorded with time- and space-resolved technique, so we obtained time-resolved, in 10(-9) s, spectra of the plasma radiation in front of the surface at 0.5 mm, 1.5 mm, 2.5 mm and 3.5 mm, respectively. Based on the spectra, we briefly discussed the characteristics of the plasma radiation in each zone, and studied the behavior of the continuum and aluminum radiation in detail, so the spatial profile of the plasma was obtained. As we found, at the beginning of the plasma coming into being, the radiation of the plasma was dominated by continuum radiation, but aluminum radiation became dominant later. Characteristic and ion radiation was much weaker than continuum radiation. The aluminum radiation lasted much longer than continuum and ion radiation. As a result, it was suggested that the absorption of continuum radiation of plasma by aluminum atoms should be the main mechanism for the formation of the aluminum double lines and the broad absorbtion spectra.