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Freeze shaft sinking is one of the main methods for the construction of vertical shaft in deep and thick topsoil. Freezing tube, frozen soil wall and shaft lining are the key to ensure the safety of freeze shaft sinking. Based on the on-site monitoring of the freeze shaft sinking project in Yuncheng coal mine in East China, this paper analyzes the variation law of freezing pressure, steel bar stress, concrete strain of the shaft lining, and frost heaving stress inside and outside the frozen soil wall in deep topsoil, and makes an in-depth analysis of the sudden change of the monitoring curves induced by the fracture of freezing tubes. The results show that: the freezing pressure in deep topsoil increases rapidly in early stage, reaching 66% - 86% of its' maximum value in 10 days, and tends to be stable after 30 days; the maximum freezing pressure generally approaches or even exceeds the initial horizontal earth pressure. The accumulation of frost heaving stress aggravates the stress and deformation of the frozen soil wall, freezing tube and shaft lining during shaft excavation, which is an important reason for the maximum freezing pressure to exceed the initial horizontal ground pressure and the fracture of freezing tube. The fracture of freezing tube causes local melting and weakening of the frozen soil wall, significantly affects the stress and deformation of the shaft lining, and induces the mutation of monitoring parameters. By means of monitoring the stress and deformation of shaft lining closely, it is feasible to judge and forewarn the fracture accident of freezing tube in time and take corresponding measures based on the sudden change of monitoring curves captured.

Ab initio calculation of the total dielectronic recombination (DR) rate coefficient from the ground state of Co-like tantalum is performed using the relativistic distorted-wave approximation with configuration interaction. The contributions to the total DR rate coefficients are explicitly calculated from the complexes of Ni-like tantalum: 3s23p63d33/23d65/2n'l', 3s23p53d10n'l', 3s3p63d10n'l', 3s23p63d84ln'l', 3s23p53d94ln'l' and 3s3p63d94ln'l' with n' ≤ 25, and 3s23p63d85ln'l' with n' ≤ 9. The l' and n' dependences of partial DR rate coefficients are investigated. The contributions from higher n' complexes are evaluated by a level-by-level extrapolation method. The total DR rate coefficients mainly come from the complex series 3s23p63d84ln'l', 3s23p53d94ln'l' and are fitted to an empirical formula with high accuracy. Comparison of the present results with those of other works shows that the previously published data underestimate significantly the DR rates of Co-like tantalum.

The ab initio calculations of electron-impact resonant excitation rate coefficients from the ground level to 54 fine-structure levels of 3d94l (l = s,p,d,f) configurations of Ni-like tantalum ion are performed by using a fully relativistic distorted-wave approximation. The configuration-interaction effects are taken into account. The decays to autoionizing levels possibly followed by autoionization cascades are also included in the calculation. The contributions from doubly-excited intermediate states of Cu-like 3l17n'l'n''l'' (n' = 4,5; n'' = 5?15) are calculated explicitly, and the contributions from high Rydberg states (n''>15) are taken into account by using n?3 scaling law. The present results should be more accurate than the existent calculations.

Dielectronic recombination (DR) cross sections and rate coefficients of He-like Kr are calculated employing the relativistic flexible atomic code, in which autoionization rates are calculated based on the relativistic distorted-wave approximation and the configuration interaction is considered. The Auger and total radiative rates of some strong resonances are listed and compared with the results from multiconfiguration Dirac–Fock and Hebrew University Lawrence Livermore Atomic Code methods. The n−3 scaling law is checked and used to extrapolate rate coefficients. We also show the variation of DR branching ratio with different DR resonances or atomic number Z. The effect of radiative cascades on DR cross sections are studied.

Ab initio calculations of dielectronic recombination (DR) rate coefficients from the ground state of Ni-like Au ion through the Cu-like 3d94ln'l' (n' = 4,5) configurations have been performed by using a relativistic atomic code FAC with configuration interaction. The DR rate coefficients through the 3d94l5f5/2 and 3d94l5f7/2 configurations are evaluated separately. The contributions from resonant and nonresonant radiative stabilizing transitions to the total rate coefficients are distinguished and discussed. The decays to autoionizing levels followed by radiative cascades are included in the calculation.

We calculate direct radiative recombination cross sections and rate coefficients for Be-like O4+, Si10+ and Na-like Fe15+ using nonrelativistic dipole approximation. In order to incorporate the screening effect due to the inner-shell electrons in the calculation, we use the distorted wave method instead of pure Coulomb approximation with effective charge. The calculated cross sections and rate coefficients are in agreement with other theoretical calculations and the experimental data.

The diffusion barriers for the single helium atom in 3d transition metals are systematically studied by effective medium theory without any adjustable parameters. In the calculation, the relaxiation effects of lattice are taken into account. The comparison of our calculated results with the available experimental data and other theoretical values shows good agreement.

A distorted-wave Born exchange (DWBE) approximation was used to calculate the electron-impact ionization cross sections and rate coefficients for the ions of . The comparison of the calculated results with the experimental data and other theoretical calculations shows that the DWBE method is valid for all the ions of neon. The results of the calculations for cross sections were fitted by empirical formulae to meet the requirements of applications. A set of improved empirical formulae were developed for the fast and accurate calculations of rate coefficients from the fit parameters of cross sections.

The effect of configuration interaction (CI) on the theoretical calculation of autoionization cross section for Li-like ions are studied in detail by employing the distorted wave Born exchange approximation. We consider the 1s22s → 1s2s2p and 1s22s → 1s2s3p transitions for C3+ and Al10+ ions. These two transitions account for the largest excitation autoionization cross section. It is found that the CI has a significant effect on the calculated results. The effect becomes larger with increasing atomic number.

The charge states of sputtered cesium and oxygen ions/atoms from metal surfaces have been discussed with the time-dependent Newns-Anderson model. The final charge state distribution has been calculated as a function of work function of the surfaces. The calculated results fit the experimental data well. Besides, the dependence of the final charge states of the sputtered oxygen particles on the surface temperature is also predicted.

The optical isotope shifts in the transition 4f4 5d 6 K9/2 -(23 537)9/2 0 (5702 A) of Nd II by collinear fast-ion-beam laser spectroscopy have been used to deduce for the first time that the mixing probabilities of the configurations 4f3 5d2 , 4f4 6p and 4f3 5d6s of the level (23 537)9/2 0 are 0.84, 0.15 and 0.01 respectively.

The optical isotope shifts of five even isotopes of neodymium have been measured by using collinear ion beam laser spectroscopy (CIBLS). Isotopically pure NdII ions with energy of 30ke V from an isotope separator were collinearly interacted with light from a tunable dye laser and selectively excited from a metastable level of 4f4 5d6 K9/2 to the (23537)9/20 level by Doppler tuning technique. The resonant excitation frequency values for each Nd isotope with mass number of 142, 144, 146, 148 and 150 were obtained. After the separation of the normal and specific mass shift and the field shift from the experimentally measured isotope shift, the configuration of the (23537)9/20 level was decomposed into 4f4 6p, 4f3 5d2 and 4f3 5d6p, and their fractions, for the first time. were determined to be 0.12-0.13, 0.88-0.85 and 0-0.02, respectively.

By using the semi-relativistic distorted-wave Born exchange method, electron impact cross sections for the Fe23+ line emission 3d5/2 → 2p3/2 are calculated. The calculation involves line formation by direct electron-impact excitation, radiative cascade, resonant excitation, and dielectronic recombination satellites with captured electron in the n ≥ 5 levels. The results show a good agreement with the recent measurements.

By using a distorted-wave Born exchange ( DWBE ) approximation method including the relativistic correction, we calculated the direct ionization and excitation autoionization cross sections of eight Na-like ions. Based on the calculated results, we present two empirical formulas with high accuracy for calculating direct ionization and excitation autoionization cross sections. Our results are in good agreement with the experiment data and other theoretical values.

A distorted -wave Born exchange (DWBE) approximation is used to calculate the resonance-ex-citation double autoionization (REDA) for the Li Isoelectronic sequence.Comparison shows good a-greement between the present calculation and experimental data and other theoretical results.In this paper,our research is focused on the effect of the configuration-mixing and radiation channel on the REDA,and the REDA contribution to the ionization process.Also their variation with ion charge Z is given.

A distorted-wave Born exchange (DWBE) approximation is used to calculate the cross sections of electron-impact ionization for Ne+,…，Ne6+.The comparison shows good agreement between theoretical and experimental results.We give empirical formulas with high precision to meet the requirements of applications.The validity of the DWBE method in lowly ionized ions and the affect of the exchange potential on the calculated results are also discussed.

Using a simpler calculation scheme, we have investigated the surface penetration barriers and bulk diffusion barriers for oxygen in the simple metals Al,Be,Ca,Mg,Zn and their oxides. The results show that the values of the barriers depend on the crystal structure of the material and on the ability of the lattice to relax during the incorporation process. By comparing the theoretical values of the barriers with the experimental ones, we found that the agreement is basically good.

The excitation autoionization of Na-like Cu ion origination from inner-shell excitations of 1s22s22p６3s→1s22s2２ｐ5３ｓ３ｌ（ｌ＝０，１，２） was investigated in some detail. The inner-shell excitation cross sections were calculated in the distorted Columob-Born exchange approximation and the target ionic states were obtained in a single configuraton approximation. The autoionizing branch ratios were calculated by using both single configuration and configuration interaction wavefunctions. The results showed that, at an incident electron energy of 1090 eV, the correlation enhancement of excitation autoionization cross sections was mainly due to 1s22s22p53s3d configuration,in which the correlation effects increasd the excitation autoionization cross sections nearly to a factor of 2. The excitation autoionization cross sections for 1s22s22p53s2 were reduced about 36% when compared with the results of single configuration approximation. Howecer, The configuration interaction had only a slight effect on the autoionization cross sections for excitation to 1s22s22p53s3p configuration.

A distorted wave born exchange (DWBE) approximation is used to calculate the cross section of electron impact ionization for atomic hydrogen. Both the energy differential cross sections and the integral cross sections from calculation are compared with the latest experimental data. The comparison shows good agreement between theoretical and experimental results. The small difference between these results is also discussed.

The charge states of Cs ions/atoms scattered from Cs/W(110) surfaces have been calculated as a function of the work function and temperature of surfaces with the aid of the time-dependent News-Anderson quantum model. The calculated results are in good agreement with the experimental data. Furthermore, the variations of charge states of the moving Cs ions/atoms approaching and leaving the surface are demonstrated and compared.

By using a distorted-wave Born exchange approximation, the direct ionizarion cross section of boron-like ions by electron impact have been calculated. The interferences between direct and exchange amplitudes make important contribution in the process of ionization. The calculated results indicate that the "Natural Phase" approximation is better than the "Maximum Interference" approximation, while the latter agrees better with experiments for some other species of ions. Compared with Coulomb-Born approximation of Moores et al., our calculation gives better agreement with the experiment data available.

The cross section of inner-shell excitation followed by auto-ionization and total ionization cross section of lithium-like ions by electron impact have been calculated by using a distorted wave Born exchange approximation. The comparison of present data with close-coupling calculation and experimental measurement is satisfactory.