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The axial and radial load capacity of axial hybrid magnetic bearing (HMB) is critical for the magnetic levitation system. In this paper, the effect of permanent magnet (PM) position on axial and radial magnetic force and stiffness in axial HMB is investigated. Six different configurations are considered and the equivalent magnetic circuits of HMBs for each configuration is built and studied based on the distribution of magnetic field and magnetic leakage. The dependence of axial and radial magnetic force and stiffness on the axial displacement, radial displacement and control current is calculated and investigated for different configurations. To validate the calculated results, the axial and radial magnetic forces for each configuration are simulated by finite element method. A good agreement between the calculated and simulated results validated the proposed magnetic circuit models.

Underground coal gasification (UCG) is a promising option for the recovery of low-rank and inaccessible coal resources. Detailed mineralogical information is essential to understand underground reaction conditions far from the surface and optimize the operation parameters during the UCG process. It is also significant in identifying the environmental effects of UCG residue. In this paper, with regard to the underground gasification of lignite, UCG slag was prepared through simulation tests of oxygen-enriched gasification under different atmospheric conditions, and the minerals were identified by X-Ray diffraction (XRD) and a scanning electron microscope coupled to an energy-dispersive spectrometer (SEM-EDS). Thermodynamic calculations performed using FactSage 6.4 were used to help to understand the transformation of minerals. The results indicate that an increased oxygen concentration is beneficial to the reformation of mineral crystal after ash fusion and the resulting crystal structures of minerals also tend to be more orderly. The dominant minerals in 60%-O2 and 80%-O2 UCG slag include anorthite, pyroxene, and gehlenite, while amorphous substances almost disappear. In addition, with increasing oxygen content, mullite might react with the calcium oxide existed in the slag to generate anorthite, which could then serve as a calcium source for the formation of gehlenite. In 80%-O2 UCG slag, the iron-bearing mineral is transformed from sekaninaite to pyroxene.

Objective: To study the protective and therapeutic antitumor immunity against hepatocellular carcinoma (HCC) with the fixed-tumor vaccine.Methods: A tumor vaccine consisting of fixed tumor cells or fixed tumor fragments combined with sustained-releasers of cytokines and a non-toxic adjuvant was developed. C57BL/6J mice were immunized intra-dermally with the vaccine on day 0 and 7, followed by intrahepatic challenge with live Hepa 1–6 cells.Results: All of 15 nonimmunized control mice developed the hepatoma. Protection of mice immunized with fixed Hepa 1–6 cells and both of IL-2/GM-CSF microspheres or further mixed with TiterMax Gold reached 80% and 87%, respectively. Mass growth of the established tumors, vaccinated twice at 5 mm in diameter, the tumor of control animals continued to grow. However, 7–10 days after the second injection of the tumor vaccine, the tumor growth was suppressed in 9 of 10 mice and then markedly reduced. Complete tumor regression was observed in 60% (6/10) of mice. Splenocytes from the control mice were not able to lyse target Hepa 1–6 cells and other tumor cells. In contrast splenocytes from the vaccinated mice exhibited a 41% lytic activity against the Hepa 1–6 cells tested at an effector/target (E/T) ratio of 5, whereas they did not exhibited such activity against the melanoma cells (B16-F1), Lewis lung carcinoma cells (LLC), renal carcinoma cells (Renca), and bladder carcinoma cells (MBT-2). The cytotoxic activity was inhibited by the treatment with anti-CD3, anti-CD8, and anti-MHC-class I monoclonal antibodies but not with anti-CD4 and anti-MHC-class II antibodies. In the Phase-I clinical trial, vaccination of HCC patients with the autologous vaccine is a well-tolerated treatment and induces fixed tumor fragment-specific immunity.Conclusion: Fixed HCC vaccination elicited protective and therapeutic antitumor immunity against HCC. The tumor vaccine elicited antigen specific CTL response lysis of the target HCC was mediated by the typical MHC-class I restricted CD8+ T cells.

Energy is important for the development of human civilization. As conventional energy exhausts, the development of clean and renewable energy, such as wind and solar becomes ever important to people’s live. The wind power has been harnessed by mankind for a long time and the associated technology is more advanced than other clean energies. Nowadays wind power increasingly attracts interests and its utilization has entered a rapid development stage. There are two types of wind turbines, namely horizontal-axis wind turbine (HAWT) and vertical-axis wind turbine (VAWT). The latter has many advantages, such as low cost, simple-structured blades, convenient installation and maintenance, and the ability to utilize wind from all directions without the need of a steering mechanism. A special VAWT implemented with magnetic suspension and self-pitch blade design will be introduced in this chapter. It not only has the advantages of traditional VAWT, but also the advantages of low threshold starting wind-speed, high wind power efficiency, etc. Discussion in this chapter includes the benefits of applying magnetic bearing technology to the wind turbine. Specifically, the entire wind turbine rotor weight can be supported by magnetic bearings. The friction of the bearings is essentially non-existence. There is no need for bearing lubrication, and the maintenance cost can be reduced. Furthermore, the magnetic suspension technology can eliminate mechanical vibration and reduce noise. Since low friction also reduces starting torque, the magnetic bearings enable producing power at lower wind speed than conventional bearings. The discussion also includes a blade-pitch adjusting technique. Conventional VAWT applies special blade adjusting mechanism which is complicated in structure, costly to fabricate and wastes power. Herein, the blades in a magnetic suspended VAWT are designed to adjust the pitch automatically and do not require any dedicated special devices. The blade pitch is adjusted naturally during rotation for the best windward angle. As a result the blades always produce the maximum thrust wind force improving the wind turbine efficiency. Thus, the magnetically suspended and self-pitched vertical-axis wind turbine will be designed with uncomplicated structure, high efficiency and low cost.

At first, the system simulation was run in one degree of freedom based on the non-linear mathematic model of active magnetic bearing (AMB). That analyzes the effect of the controller parameters to the AMB performance and response waveforms of the axis in different parameters. Further, the motional waveform of the axis in two directions (vertical and horizontal) was simulated for the dynamic performance of the axis in the initial levitation.