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Terbium gallium garnet (Tb3Ga5O12, TGG) crystal can be used to fabricate various magneto-optical devices due to its optimal Faraday effect. In this work, 400-keV He+ ions with a fluence of 6.0 × 1016 ions/cm2 are irradiated into the TGG crystal for the planar waveguide formation. The precise diamond blade dicing with a rotation speed of 2 × 104 rpm and a cutting velocity of 0.1 mm/s is performed on the He+-implanted TGG planar waveguide for the ridge structure. The dark-mode spectrum of the He+-implanted TGG planar waveguide is measured by the prism-coupling method, thereby obtaining the relationship between the reflected light intensity and the effective refractive index. The refractive index profile of the planar waveguide is reconstructed by the reflectivity calculation method. The near-field light intensity distribution of the planar waveguide and the ridge waveguide are recorded by the end-face coupling method. The He+-implanted and diamond blade-diced TGG crystal planar and ridge waveguides are promising candidates for integrated magneto-optical devices.

Atomic data of highly charged ions (HCIs) offer an attractive means for plasma diagnostic and stars identification, and the investigations on atomic data are highly desirable. Herein, based on the fully relativistic multi-configuration Dirac–Hartree–Fock (MCDHF) method, we have performed calculations of the fine-structure energy levels, wavelengths, transition rates, oscillator strengths, and line strengths for the lowest 21 states of 3p63d8–3p53d9 electric dipole (E1) transitions configurations in Fe-like ions (Z = 57, 60, 62, 64, 65). The correlation effects of valence–valence (VV) and core–valence (CV) electrons were systematically considered. In addition, we have taken into account transverse-photon (Breit) interaction and quantum electrodynamics (QED) corrections to treat accurately the atomic state wave functions in the final relativistic configuration interaction (RCI) calculations. Our calculated energy levels and transition wavelengths are in excellent agreement with the available experimental and theoretical results. Most importantly, we predicted some new transition parameters that have not yet been reported. These data would further provide critical insights into better analyzing the physical processes of various astrophysical plasmas.

Combat simulation test is the main means of evaluating command information systems. In order to improve the intelligence and efficiency of simulation experiment, the method of applying intelligent speech interaction technology (ISIT) to the simulation experiment automation process is proposed. The application processes of speech instruction recognition, instruction element analysis, data instruction generation and speech synthesis feedback are designed based on human-machine ISIT. Meanwhile, taking the air combat command and guidance scene an example, the command and guidance voice instruction database is constructed, and the speech interaction simulation experiment is designed and verified. The results show that ISIT can effectively reduce the number of commanders and operators in air combat simulation test, and improve test efficiency.

The energy levels, transition energies, transition probabilities, weighted oscillator strengths, and line strengths of Li-like ions (Z = 7–11) in dense plasmas are investigated in this work. The relativistic effects and electron correlation effects are described by the MCDHF method. The ion sphere model is applied to include the dense plasma screening effect. The ground configuration 1s22s and the excited 1s22p, 1s23l (l = 0–2) are considered. The configuration sets are enlarged until n = 7 where the calculated energy levels have converged. The critical free electron densities of 1s23d states are estimated. Except for 1s23s–1s23p transitions, the transition energies for Δ n = 0 increase, and for Δ n ≠ 0 decrease with increasing free electron densities. For 1s23s–1s23p transitions, the spectra show blue-shift at lower free electron densities and red-shift at higher free electron densities, and the energy level crossing phenomens are observed at higher free electron densities.

Capacitive Deionization (CDI), a recently developed water treatment technology, has proved to be superior to traditional desalinization processes such as reverse osmosis (RO) in terms of high environmental friendliness, simple operation, and low energy consumption. This paper reviews the progress of research into CDI technology with focus on electrode materials and factors affecting CDI such as voltage and plate spacing. It also discusses existing problems and predicts the future development direction of this technology.

Based on the density functional theory, the energy band and electronic structure of β-CuGaO2 are calculated by the modified Becke-Johnson plus an on-site Coulomb U (MBJ + U) approach in this paper. The calculated results show that the band gap value of β-CuGaO2 obtained by the MBJ + U approach is close to the experimental value. The calculated results of electronic structure indicate that the main properties of the material are determined by the bond between Cu-3d and O-2p energy levels near the valence band of β-CuGaO2, while a weak anti-bond combination is formed mainly by the O-2p energy level and Ga-4s energy level near the bottom of the conduction band of β-CuGaO2. The β-CuGaO2 thin film is predicted to hold excellent photovoltaic performance by analysis of the spectroscopic limited maximum efficiency (SLME) method. At the same time, the calculated maximum photoelectric conversion efficiency of the ideal CuGaO2 solar cell is 32.4%. Relevant conclusions can expand β-CuGaO2 photovoltaic applications.

To realize zero boil-off storage of cryogenic liquids, a cryocooler that can achieve a temperature below the boiling point temperature of the cryogenic liquid is generally needed. Taking into account that the efficiency of the cryocooler will be higher at a higher operating temperature, a novel thermal insulation system using a sandwich container filled with cryogenic liquid with a higher boiling point as a cold radiation shield between the cryogenic tank and the vacuum shield in room temperature is proposed to reduce the electricity power consumption. A two-stage cryocooler or two separate cryocoolers are adopted to condense the evaporated gas from the cold shield and the cryogenic tank. The calculation result of a 55 liter liquid hydrogen tank with a liquid nitrogen shield shows that only 14.4 W of electrical power is needed to make all the evaporated gas condensation while 121.7 W will be needed without the liquid nitrogen shield.

A two-stage gas-coupled Stirling-type pulse tube cryocooler (SPTC) driven by a linear dual-opposed compressor has been designed, manufactured and tested. Both of the stages adopted coaxial structure for compactness. The effect of a cold double-inlet at the second stage on the cooling performance was investigated. The test results show that the cold double-inlet will help to achieve a lower cooling temperature, but it is not conducive to achieving a higher cooling capacity. At present, without the cold double-inlet, the second stage has achieved a no-load temperature of 11.28 K and a cooling capacity of 620 mW/20 K with an input electric power of 450 W. With the cold double-inlet, the no-load temperature is lowered to 9.4 K, but the cooling capacity is reduced to 400 mW/20 K. The structure of the developed cryocooler and the influences of charge pressure, operating frequency and hot end temperature will also be introduced in this paper.

This paper presents the fully differential cross sections (FDCS) for 102eV electron impact single ionization of helium for both the coplanar and perpendicular plane asymmetric geometries within the framework of dynamically screened three-Coulomb-wave theory. Comparisons are made with the experimental data and those of the three-Coulomb wave function model and second-order distorted-wave Born method. The angular distribution and relative heights of the present FDCS is found to be in very good agreement with the experimental data in the perpendicular plane geometry. It is shown that dynamical screening effects are significant in this geometry. Three-body coupling is expected to be weak in the coplanar geometry, although the precise absolute value of the cross section is still sensitive to the interaction details.

The magnetic properties and microstructure of triple C/CoCrTa/Ti perpendicular recording films have been studied. Magnetic measurements show that the optimal thickness of Ti underlayer is 40 nm and that of CoCrTa is 35 nm. The optimal value of substrate temperature is found to be 400°C. A suitable Ti underlayer causes a magnetic layer to have a near-perfect hcp texture, with Co grains in the (002) preferred orientation. The film with needle-like grains is more suitable for perpendicular recording films.

In this paper, the triple differential cross section for the low-energy electron impact ionization of the Li+ ion is considered in the coplanar equal energy-sharing kinematics at an incident energy of 114.083 eV. The emergence of structures in the calculated cross sections is explained in terms of isolated two-body final-state interactions and three-body coupling. The cross section shows two peaks originating from `classical' sequential two-body collisions. The position of these peaks is determined by two-body final-state interactions. In addition, it is demonstrated that the signature of three-body interactions is carried by the magnitude and ratio of these two peaks. The direct and exchange amplitudes are also considered.

The inoculation of short-cut denitrifying polyphosphate-accumulating organisms (DPAOs) mainly included two-phase inoculation and three-phase inoculation. The short-cut denitrifying phosphorus removal bacteria were quickly inoculated by sequencing batch reactor (SBR) to treatment domestic wastewater. The results showed that the average effluent concentration of TP was 0.85 mg/L after 132 cycles by 44 days in two-phase inoculation. The removal rates of NO2 --N, TP and COD were 94.73%, 95.47% and 89.96% after 126 cycles by 42 days in three-phase inoculation, and the effluent concentrations were separately 1.31 mg/L, 0.45 mg/L and 17.07 mg/L, which reached the first A class requirement of Urban sewage treatment plant pollutant discharge standard. It was indicated that the efficiency of three-phase inoculation was higher. Anoxic phosphorus uptake was influenced seriously by anaerobic residual carbon, and it was the difference of the two inoculations.

The softening process of the second kind of dumbbell domains(IIDs) in garnet bubbles films subjected to an in-plane field Hip at different static bias field Hb was studied experimentally. It was found that when Hb is larger, the remaining percentage of IID, RIID, drops sharply at a certain Hip, and with the increase of Hb the drop occurs at lower Hip and becomes more intensive. We have confirmed that this is related to the "spontaneous-shrink" of IIDs, which plays an important role for the breakdown of vertical Bloch line chains of IIDs subjected to joint fields Hip and Hb.

For the ordinary hard bubbles (OHBs) of garnet bubble films, the annihilation of the vertical-Blochline (VBL) chains in their walls subjected to joint static bias field Hb and in-plane field Hip was experimentally studied. The curves of two critical in-plane fields, Hip(1) and Hip', vs Hb were measured. By means of the so-called "head-cut" and "tail-cut" experiments designed in this work, it was verified that for the OHBs subjected to Hip, their VBL chains with different lengths lose VBLs and become shorter simultaneously. It was also verified that the critical in-plane fields Hip(1) and Hip' correspond to the breakdown of the shortest and longest VBL chains of OHBs, respectively.

An exhaustive study of optical emission from a nitrogen arc produced by an arc-heated beam source is reported. Atomic nitrogen emission lines in the spectral region provide unequivocal evidence that the arc-heated beam source generates an appreciable flux of nitrogen atoms. Experimental results show that the ratio of [N] to increased as the arc pressure decreased. It is believed that this is because of the reduced probability of recombination of [N] atoms. Using this arc-heated beam source for pulsed laser deposition (PLD) film growth, we have synthesized carbon nitride and other nitride films with a high nitrogen content. AES and XPS results indicate that composition ratios ([N]/[C]) in the deposited films were between 0.2 and 0.6. It has been considered that [N] atoms, rather than molecules in the arc, are the most likely species responsible for the synthesis of nitride films.

High spin states in neutron-deficient 117Xe have been studied by using in-beam γ spectroscopy method. A new positive-parity rotational band has been identified. It decays into the yrast νh11/2 band via five electric dipole transitions. The magnitudes of these E1 transitions are extracted and they are much enhanced compared to the normal E1 transitions. This is taken as an evidence for octupole correlations in 117Xe.

The synthesis of covalent carbon nitride films becomes an important subject in the materials research field. As a new synthetic method two low-energy (400 and 1000 eV) nitrogen ion beams are used to bombard on C60 thin films individually. The bombarded films are used for Raman and x-ray photoelectron spectroscopy (XPS) measurements. The results of the analyses show that under the bombardment of 400 eV nitrogen ion beam, the film still contains a large amount of undestructed C60 molecules. In the case of 1000 eV bombardment, only a little amount of C60 molecules is kept undestructed. The experimental results also show that the destructed carbon species will combine chemically with nitrogen ions to form stable covalent carbon nitride, confirmed by the Raman peaks of, e.g., 2240 cm-1. The XPS N1s and C1s lines also indicate the formation of covalent carbon nitride in the bombarded films.

The stability of vertical Bloch line (VBL) chains was statistically studied for all three types of hard domains in garnet bubble films subjected to an in-plane field Hip. With a set of integrate data taken from seven bubble samples and with two typical figures of a sample, four main features of the behavior of VBL chains subjected to Hip were summarized.

High spin states of the odd-odd 162Lu nucleus have been studied via 147 Sm(19F, 4nγ) reaction at 95 MeV beam energy. Level scheme for yrast band based on π[h11/2]ν[i13/2] quasiparticle configuration was established up to Iπ = (23-) for the first time. This band shows the signature inversion in energy before backbending generally appeared in this mass region. It is stressed that the signature splitting in 162 Lu is larger than that in 160 Tm nucleus.

We have studied the microstructure and photoluminescent properties of porous Si. High resolution observations revealed that the microstructure of porous Si consists with nano-crystallites Si embedded in the surrounding amorphous matrix. The structure of nano-crystallites of porous Si is not consistent with the usual diamond structure of bulk Si. The photoluminescence from porous Si is due to the quantum confinement of carriers in this structure.

The high-spin states in 197Bi have been studied with the 187Re(16O,6n) reaction at 16O energies from 85 to 105 MeV. In-beam measurements of γ-ray excitation functions, γ-γ-t coincidences and γ-ray angular distributions were carried out with six BGO(AC)HPGe detectors and one intrinsic Ge planar detector. Eleven new transitions and three new isomers were observed, and a level scheme for 197Bi was established. Some differences between the present work and the previous results were found.

The phenomenon of multiple rescatterings in the process of high-order harmonic generation from a helium atom with a long wavelength is investigated by solving the time-dependent Schrodinger equation and the classical equation of motion. The results present the rule of cutoff energies for the multirescattering events. What is more, the physical picture of the multiple rescatterings is built and the physical mechanism is revealed in detail. Further studies show that the multiple rescatterings can be manipulated effectively and the intra-cycle interference of multiple rescatterings is weakened simultaneously when the initial state is prepared in the superposition state. Additionally, the long quantum path is verified to play an important role in the multiple rescattering processes.

Experiments were statistically carried out on the behavior of the vertical-Bloch-line (VBL) chains of the first kind of dumbbell domains (IDs) in garnet bubble films subjected to an in-plane field, Hip. It was found that for IDs the critical in-plane field, (H'ip)ID, above which their VBL chains disappear, is the same as that of ordinary hard bubbles (OHBs), H'ip. However, for IDs, the critical range of Hip for VBL chain softening is larger than that of OHBs. Besides, we also found some details of the softening process, e.g., the collapse field range of the remaining IDs shrinks rapidly towards H0,max, and this very narrow range can maintain until all IDs are softened.

The highly photo-sensitive characteristics of porous silicon (PS) were observed. The transient behaviors of photoconductivity in horizontal and perpendicular directions of PS surface were very different, through both of them include two decay components. The photoconduction spectra at room temperature and 14.5 K show that characteristics of PS are different from those of silicon substrate. The difference may be attributed to quantum confinement effect in nano-size microstructures of PS.

An experiment was statistically performed on the annihilation of vertical-Bloch-line (VBL) chains in the walls of the second kind of dumbbell domains (IIDs) subjected to an in-plane field Hip. It was again confirmed that there is a critical in-plane field H'ip, above which all VBL chains of hard domains in garnet bubble films, including IIDs, disappear. Just like ordinary hard bubbles (OHBs), it was also found that there exists a critical range of Hip, from (Hip)ID to H'ip, for IID softening. Over this range, with the increase of Hip, more and more IIDs are softened, accompanied by the successive appearance of the first kind of dumbbell domains, OHBs and soft bubbles. In addition, for the five samples tested, the ratio, H'ip/(Hip)ID, is obviously greater than √2.