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Excitation functions have been measured for different projectile-like fragments produced in Al-27(F-19,x)y reactions at incident energies from 110.25 to 118.75 MeV in 250 keV steps. Strong cross section fluctuations of the excitation functions are observed. The cross- correlation coefficients of the excitation functions for different atomic number Z and for different scattering angle theta(cm) have been deduced. These coefficients are much larger than the statistical theoretical calculated ones. This indicates that there are strong correlations between different exit channels in the dissipative heavy ion Collision of Al-27(F-19,x)y.

Excitation functions are measured for different charge products of the 19F+27Al reaction in the laboratory energy range 110.25–118.75 MeV in steps of 250 keV at θlab = 57°, 31° and −29°. The coherence rotation angular velocities of the intermediate dinuclear systems formed in the reaction are extracted from the cross section energy autocorrelation functions. Compared the angular velocity extracted from the experimental data with the ones deduced from the sticking limit, it is indicated that a larger deformation of the intermediate dinuclear system exists.

Choosing 7Li and 12C heavy ions respectively with different linear energy transfer (LET) values, purified plasmid DNA samples in aqueous solution are irradiated with various doses. The atomic force microscopy (AFM) is used for analysis of DNA fragments induced by both the kinds of heavy ions. There is a change of three forms of DNA, i.e. supercoiled, open circular and linear form, as the dose is observed. The distribution function of DNA fragment length is obtained for the first time and fitted with the Tsallis entropy statistical theory. The result indicates that AFM is a useful tool for analysis of the short fragment of DNA, high-LET heavy ion radiation induces DNA double strand breaks (DSBs) more effectively, and the distributions of the DSBs are more local and dense in comparison with low-LET radiation.

Two independent excitation function measurements have been performed in the reaction system of 19F+93Nb using two target foils of the same nominal thickness. We measured the dissipative reaction products at incident energies of 102 through 108 MeV with a step of 250 keV. The variance of energy autocorrelation functions of the reaction products was found to be three times of that originated from the randomized counting rates. By analysing the probability distributions of the deviations in the measured cross sections, we found that about 20% of all the deviations exceeds three standard deviations. This indicates that the non-reproducibility of the cross sections in the two independent measurements is of a statistical significance but not originated from randomized fluctuation of counting rates.

Two independent measurements of cross sections for the 19F+93Nb dissipative heavy ion collisions have been performed at incident energies from 100 to 108 MeV in steps of 250 keV. In the two measurements, two independently prepared targets were used. All other experimental conditions were identical in both experiments. The data indicate that non-reproducibility of the non-self-averaging oscillation is yielded in the two measurements. This supports the recent theoretical predictions of spontaneous coherence, slow phase randomization and extreme sensitivity in highly excited complex quantum systems.

Hydrogen and other elements in SixNyHz foils have been simultaneously measured by using a single E(gas)-E(PSD) telescope and heavy 127I ion beam in elastic recoil detection analysis (ERDA). Hydrogen is measured in the non-coincidence spectrum of E(PSD), and other elements from the ΔE−E coincidence spectrum. The composition and depth profiling of the foils are obtained from the simulated spectra.

Excitation functions of the projectile-like fragments in the dissipative reaction 19F + 51V have been measured from 102.25 MeV to 109.50 MeV in 250 keV steps. The corresponding energy coherence widths Γ were extracted by means of the energy autocorrelation function method. The dependence of Γ on the degree of freedom of neutron excess N Z and the dependence of the charge number Z on the angular momentum coherence width γ are presented and discussed.

Angular distributions of fragments B, C, N, O, F, Ne, Na, Mg and Al induced by the collision of F-19+Al-27 at 114 MeV have been measured. Angular dispersion parameters are extracted from the experimental data and compared with the theoretical ones. The dynamic dispersions for dissipative products depend strongly on the charge number Z of the fragments.

Excitation functions for projectile-like fragments from F-19+V-51 reaction have been measured at 102.25 to 109.50MeV in 250keV steps. A TOF+(Delta E - E) telescope at theta(L) = 21.7 degrees is used to identify atomic number Z and mass number A of ejectiles simultaneously. Fluctuations of the dissipative cross section for a. series of isotopes are observed. Their coherence energy widths are extracted by generalized statistical fluctuation analysis and the dependence on mass number and on N/Z values are observed for the first time.

Conflict detection and displacement are significant operators to maintain spatial relationship of map elements in cartography. At present, much attention has been paid to element division for local conflict detection and progressive displacement. By deeply observation, analysis and experiment, many models have been found good applicability for cartography, such as structure mechanics model, snake model, delaunay model, et al. But local conflict detection and progressive displacement still need more researches to achieve automatic cartographic generalization. In this paper, electric field model is proposed firstly to try conflict detection and displacement. Distribution of electric field is suit for conflict detection and displacement of map elements, since conflict occurs in local and changes with range. The main idea is to take conflict of road and building elements as that of points scattered from lines, and points represent particles with electric power. Conflict can be expressed by electric repulsion between particles. On the basis of electric field model, an algorithm and workflow is designed to verify the model effectiveness. The experiment concludes that the quantitative relationship of scale factor to discretization step and displacement amount is credible, and progressive displacement algorithm is effective for conflict detection and displacement.

The Beijing Q3D magnetic spectrometer has been used for many experiments in this laboratory. It is found that the locations of the effective field boundaries (EFB) of the dipole magnets with the floating snakes are shifted towards the magnets, comparing with the design. Their effects on the ion-optical performances of the spectrometer were checked by the calculation with the program RAYTRACE and a method to reoptimize the performance with the program is described. The experimental investigation of the spectrometer performances has been carried out by the so-called “experimental ray-tracing” method. A method to adjust experimentally the focal plane angle in a finite region is proposed. The focal plane angle of 47.5° has been adjusted successfully to the original designed value, 45°. By the use of this method not only the various features of the spectrometer are well determined, but also the empirical field-setting for every adjustable magnetic element is uniquely set up. Some of the applications are mentioned in this paper.