[en] According to the designed cold neutron guide system and by means of simulating calculation and analyzing, the most important parameters for design were got which are available range of neutron wavelength, flux at the sample position and resolution of energy. Based on these parameters, the specifications of the space layout of the spectrometer and its main components were given out, including transmission range of energy and momentum, angle range and mosaic spread of monochromator and analyzer, scattering angle of the sample table, collimation angle of collimators, and the background and dose. (authors)

[en] At present, neutron diffraction method is the unique and nondestructive method that can directly measure the residual stress distribution in deep materials and engineering components. It has an important application in engineering. A simulation of the flux at the position of the sample table was reported, and the resolution of the residual stress instrument was computed at the same time. The effect of the parameters of the second collimator on the flux at the sample position and the resolution of the instrument have been analyzed. The result indicated that the second collimator empress much on the neutron flux and the instrument resolution is well when the sample's diffraction angle is less than 120°. (authors)

[en] Ti-50.6 at.% Ni shape memory alloy specimens were irradiated under the austenite state (parent phase) using a tandem accelerator by 18 MeV protons with doses of 1.53 x 10¹³ and 1.53 x 10¹⁴ H⁺/cm². The microstructure and phase transformation of the specimens before and after irradiation were examined by transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). After the irradiation the parent phase (austenite) was stabilized. R-phase transformation start temperature and the reverse martensitic transformation finish temperature decreased with the increasing proton fluence. They decreased about 13 K and 6 K at a dose of 1.53 x 10¹⁴ H⁺/cm², respectively. The reverse martensitic transformation start temperature and R-phase transformation finish temperature were not affected by the proton irradiation. There is no observable change in the microstructure after irradiation for the low atom displacement probability. The variation of the transformation temperature was assigned to the local stress fields and change in the ordering degree of lattice generated by proton irradiation

[en] With a ¹⁰⁹Cd source, the Compton scattering intensity and the X-ray fluorescence intensity of Fe in coal were used to determine the ash content in coal. The maximum deviation was less than ±1.5% for the ash contents from 6% to 50%, and the relative error in comparison with the gravimetry was less than ±1.5%. In this paper, the use of different radioisotope sources to determine the ash contents was also discussed

[en] The measurement of activity in water sample needs a water standard sample to calibrate a γ-spectrometer used to analysis the activity, but in ordinary laboratory the water standerd sample is generally absent. The method using a soil standard sample instead of a water standerd sample has beenpresented in the paper, and by Monte carlo simulation,it has been calculated that calibration error arising from the substitute because of the significant difference of compositions and densities in the two sort of samples. The error is 12% for activity measurement of ²³⁸U, and the errors are less than 5% for the other nuclides of ²³²Th, ²²⁶Ra and ⁴⁰K in water sample. The calibration errors can be corrected by the method presented in the paper. (authors)

[en] Monochromator is one of the most important parts of neutron Triple-Axis Spectrometer (TAS), and its performance has an effect on data detecting and analyzing. We have investigated some monochromator parameters of neutron TAS in China, ILL and LLB. Because there is different location and focus on wavelength in experiment, appropriate neutron source and location limit should be taken into account in the design of monochromator. According to the basic principle of the focusing monochromator, investigation and analysis of typical monochromator in the world, including size, crystal, research capability, we can offer references on the type and parameters for the construction of triple- axis spectrometer monochromator. (authors)

[en] It introduces a data treatment software for small-angle scattering-PXY. One of the advantages is that two dimensional data treatment can be performed. For a sample data, two dimensional data treatment was performed, and the results were analyzed. Also the SANS experiment of wavelength calibration of the AgBE powder was carried out. Using PXY program, data treatment of the dataset was performed and the results were analyzed. (authors)

[en] The method of calculation resolution of triple-axis spectrometer are described. The neutron wavevector, horizontal divergency of collimator, energy and momentum transfer are considered. The results show that resolution decrease with increasing wavevector and horizontal divergency of collimator. The best energy resolution is 23 μeV. The layout of TAS determine the orientation of the resolution function in scattering space, but not affect the energy resolution. The resolution ellipse rotate with change of energy and momentum transfer. Calculation of resolution is important for designing the spectrometer and experiment. (authors)

[en] The electrical and mechanical characteristics of the wire-to-plate surface dielectric barrier discharge and the induced ionic wind are investigated experimentally. The different temporal behaviors in positive and negative half-cycles are studied by time-resolved images. It is shown that the discharge and the light emission are generally stronger in the positive half cycle. The discharge is inhomogeneous and propagates in streamer mode; however, in the negative half-cycle, the discharge appears visually uniformly and operates in the diffuse mode. The surface discharge can produce ionic wind about several m/s above the dielectric surface. There exists an optimal width of the grounded electrode to produce a larger plasma area or active wind region. Increasing of the applied voltage or normalized dielectric constant leads to a larger wind velocity. The performance of ionic wind on flow control is visualized by employing a smoke stream. (paper)

[en] Purpose: To evaluate the clinical value of integrated positron-emission tomography and computed tomography(PET/CT) in diagnosis and Staging of patients with non-small-cell lung cancer and to compare the diagnostic and Staging accuracy with PET alone. Methods: PET/CT was performed in 42 patients (6 women, 36 men; mean age ±SD, 57.9 ±12.7 y) with proven or suspected non-small-cell lung cancer. All studies were retrospectively reviewed by two moderately experienced physicians unaware of the clinical information. PET/CT and PET images were evaluated independently and separately. Focal fluorodeoxyglucose (FDG) uptake on attenuation-corrected PET images was scored on a 5-point scale (0 = definitely benign, 1 = probably benign, 2 = equivocal, 3 = probably malignant, 4 = definitely malignant). PET/CT images were then reviewed. Comparison was performed on a lesion-by-lesion basis. Accuracy was evaluated on the basis of follow-up, histopathologic findings or at least one other imaging method. Tumor-node-metastasis (TNM) stage was assigned on the basis of image analysis. Results: A total of 201 foci with abnormal FDG uptake were noted, two of which were seen only on PET/CT images. The sensitivity, specificity and accuracy for detection of primary cancer were 94, 100, and 95% with PET/CT. PET/CT provided additional information over the separate interpretation of PET and CT in 24 patients (57%) with 57 sites (28%). In comparison with PET, the frequency of equivocal and probable lesion characterization was reduced by 57% (63 to 27) with PET/CT The frequency of definite lesion characterization was increased by 23% (141 to 174) with PET/CT Overall correct staging increased from 81% to 89% with PET/CT on a patient-by-patient analysis. Conclusions: Compare to PET alone, PET/CT improves the accuracy in the diagnosis and staging of non-small-cell lung cancer. More definitely normal and definitely abnormal lesions were identified with PET/CT than with PET alone. (authors)