The quantitative analysis of X-ray fluorescence (XRF) spectra is studied using the partial least-squares (PLS) method. The characteristic variables of spectra matrix of PLS are optimized by genetic algorithm. The subset of multi-component characteristic spectra matrix is established which is corresponding to their concentration. The individual fitness is calculated which combines the crossover validation parameters (prediction error square summation) and correlation coefficients (R2). The experimental result indicates that the predicated values improve using the PLS model of characteristic spectra optimization. Compared to the nonoptimized XRF spectra, the linear dependence of processed spectra averagely decreases by about 7%, root mean square error of calibration averagely increases by about 79.32, and root mean square error of cross-validation averagely increases by about 14.2.

We use complementary analysis techniques to determine the structure of nanometric periodic multilayers and particularly their interfaces. We focus on Co-based multilayer which can be used as efficient optical component in the extreme ultraviolet (EUV) range. The samples are characterized using reflectivity measurements in order to determine the thickness and roughness of the various layers, X-ray emission and nuclear magnetic resonance (NMR) spectroscopies to identify the chemical state of the atoms present within the stack and know if they interdiffuse. Results are validated through the use of destructive techniques such as transmission electron microscopy or secondary ion mass spectrometry.

K-shell X-ray emission from a Cu nanowire target irradiated by an ultraintense femtosecond laser pulse is studied using an elliptically bent quartz crystal and imaging plate. The designed bent crystal spectrometer has better spectral resolution, which is higher than 1 000. The absolute K radiation photon yields are obtained from the experimental results and the Monte-Carlo model. The conversion efficiency of the Cu K line is estimated to be 0.019% from the interaction of 4 J, 50-fs laser pulse irradiated on a Cu nanowire target. The high yield of K shell X-ray has important applications in X-ray emission source.

According to the X-ray fluorescence (XRF) spectral characteristics of heavy metals in soil, the application of XRF spectra de-noising using biorthogonal wavelet packet transform technology is analyzed. Wavelet pack decomposition and threshold setting are particularly discussed. Through spectra de-noising, the linear fitting relationship between concentration and intensity of Ni is meliorated. Experimental results demonstrate that this method can effectively overcome the noise interference and preserve characteristic spectra. This method is very useful to increase the accuracy of quantitative analysis, especially for analyzing trace elements in soil.

The features of an attosecond extreme ultraviolet (XUV) field are encoded in the attosecond XUV spectrogram. We investigate the effect of the temporal structures of attosecond XUV fields on the attosecond streaking spectrogram. Factors such as the number of attosecond XUV pulses and the temporal chirp of attosecond XUV pulses are considered. Results indicate that unlike the attosecond streaking spectrogram for an attosecond XUV field with two pulses of a half-cycle separation of streaking field, the spectrogram for the attosecond XUV field with three pulses demonstrates fine spectral fringes in separated traces.

We report the luminescence properties and decay profiles of Ce:YAlO₃, Mn:YAlO₃; and Ce,Mn:YAlO₃ crystals grown by Czochralski method. The spectroscopic properties show that both Mn²⁺ ions and Mn⁴⁺ ions exist in Mn:YAlO₃ and Ce,Mn:YAlO₃ crystals. The Mn²⁺ ions have a broad emission band of 60 nm in Mn-doped YAlO₃ crystal at 530 nm. The luminescence spectra also indicate that there is significant energy transfer between Ce³⁺ and Mn⁴⁺ in Ce,Mn:YAlO₃ crystal. Because of the energy transfer, the first decay component in Ce,Mn:YAlO₃ decreases from 24.5 to 10.8 ns, which is much faster than that of Ce:YAlO₃.

YAG:Ce crystal with a diameter of 110 mm is successfully grown by the temperature gradient technique (TGT). The effects of annealing on the luminescence efficiency of YAG:Ce crystal are investigated, and the optimal annealing temperature and atmosphere are obtained. The mechanism of variation behavior of the luminescence efficiency of YAG:Ce under different annealing conditions is discussed and some details on the luminescence associated with color centers are analyzed.

Raman spectra are used for studying the structure and protein, nucleic acid, lipid, and carbohydrate contents, while cervical cancer cells irradiated by X rays of different doses are cultivated for 24 h. After irradiation by X rays, the following results are obtained. (1) Some 12-Gy groups move to the 1237-cm-1 band in compared with the control group’s 1240-cm-1 band; after irradiation by 6-Gy X ray, the 1662-cm-1 band of amide I has a blue shift of 10 cm-1 The above two parts show that because of X ray irradiation, some proteins’ random coil structures have transformed into \beta folding. (2) The 759-cm-1 band disappear in the 6-Gy group; the 570-cm-1 band of every group has a red shift, but the changes in intensity are different; the 1335-cm-1 band in every group has a blue shift, and all their intensities increase. These show that although the 570-, 759-, and 1335-cm-1 bands all belong to the tryptophan residue indole ring vibration, the molecular vibration energy structures which produce scattering lights are different. (3) The 786-cm-1 band only has a blue shift of 3 cm-1 in the 6-Gy group, and the non-hydrogen band of the phosphoric acid diester (O=P=O) increases. The frequency deviation of the 1089-cm-1 band is erratic, and the bent symmetry stretch vibration conformation of phosphoric acid diester key (O=P=O) in the nucleic acid is complex. (4) The 1570-cm-1 band has a blue shift, and its intensities all decrease, while the C=C conjugated duplet bond oxidizes, and the content of C=C decreases.