Recyclable transmission line (RTL) and linear transformer driver (LTD) development for Z-pinch inertial fusion energy (Z-IFE) and high yield.

Z-Pinch Inertial Fusion Energy (Z-IFE) complements and extends the single-shot z-pinch fusion program on Z to a repetitive, high-yield, power plant scenario that can be used for the production of electricity, transmutation of nuclear waste, and hydrogen production, all with no CO{sub 2} production and no long-lived radioactive nuclear waste. The Z-IFE concept uses a Linear Transformer Driver (LTD) accelerator, and a Recyclable Transmission Line (RTL) to connect the LTD driver to a high-yield fusion target inside a thick-liquid-wall power plant chamber. Results of RTL and LTD research are reported here, that include: (1) The key physics issues for RTLs involve the power flow at the high linear current densities that occur near the target (up to 5 MA/cm). These issues include surface heating, melting, ablation, plasma formation, electron flow, magnetic insulation, conductivity changes, magnetic field diffusion changes, possible ion flow, and RTL mass motion. These issues are studied theoretically, computationally (with the ALEGRA and LSP codes), and will work at 5 MA/cm or higher, with anode-cathode gaps as small as 2 mm. (2) An RTL misalignment sensitivity study has been performed using a 3D circuit model. Results show very small load current variations for significant RTL misalignments. (3) The key structural issues for RTLs involve optimizing the RTL strength (varying shape, ribs, etc.) while minimizing the RTL mass. Optimization studies show RTL mass reductions by factors of three or more. (4) Fabrication and pressure testing of Z-PoP (Proof-of-Principle) size RTLs are successfully reported here. (5) Modeling of the effect of initial RTL imperfections on the buckling pressure has been performed. Results show that the curved RTL offers a much greater buckling pressure as well as less sensitivity to imperfections than three other RTL designs. (6) Repetitive operation of a 0.5 MA, 100 kV, 100 ns, LTD cavity with gas purging between shots and automated operation is demonstrated at the SNL Z-IFE LTD laboratory with rep-rates up to 10.3 seconds between shots (this is essentially at the goal of 10 seconds for Z-IFE). (7) A single LTD switch at Tomsk was fired repetitively every 12 seconds for 36,000 shots with no failures. (8) Five 1.0 MA, 100 kV, 100 ns, LTD cavities have been combined into a voltage adder configuration with a test load to successfully study the system operation. (9) The combination of multiple LTD coaxial lines into a tri-plate transmission line is examined. The 3D Quicksilver code is used to study the electron flow losses produced near the magnetic nulls that occur where coax LTD lines are added together. (10) Circuit model codes are used to model the complete power flow circuit with an inductive isolator cavity. (11) LTD architectures are presented for drivers for Z-IFE and high yield. A 60 MA LTD driver and a 90 MA LTD driver are proposed. Present results from all of these power flow studies validate the whole LTD/RTL concept for single-shot ICF high yield, and for repetitive-shot IFE

DEVELOPMENT AND BIOLOGICAL TESTING OF NEW SCAFFOLDS FROM BIODEGRADABLE MATERIALS

The new gel-sublimation technique for preparation porus biodegradable scaffolds (hydroxybutyrate-co-hydro- xyvalerate) is presented. The scaffolds with multi-mode internal structure have the of porus sizes varied from ~100 microns up to ~100 nanometers and the porosity in a range of 80–90%. A few techniques for modification of 3D scaffolds by gas discharge plasma are developed and optimized: the microsecond dielectric barrier dischar- ge, the semi-self-maintained discharge supported by an electron beam; the nanosecond dielectric barrier dischar- ge. Biological tests including red blood cell hemolysis and cytotoxicity analysis have shown the possibilities of scaffolds applications for cell-based technologies

PHYSICAL METHODS OF PRODUCTION AND MODIFICATION OF BIOPOLYMER MATRIXES

The conditions which are necessary for successful functioning of implants based on polymer matrix having the structure of a chaotic three-dimensional grid are analyzed. The investigation is aimed on the development of techniques for manufacturing the volumetric structured matrixes from polymer biocompatible materials and techniques of implant creation by electro-physical surface treatment of the matrix structure with the purpose of management of their biochemical and biological activity. Morphological characteristics of the matrixes, produced by the method of freeze-drying of the polymeric gel are reported. The complex energy system created for volumetric discharges generation in the structured heterogeneous substances is described

Measuring of spatio-temporal characteristics Z-pinch from deuterated polyethylene

On the S-300 installation at currents up to 2 MA with rise time 100 ns, the investigation of the formation process of high-temperature plasma in fast Z-pinch was carried out. The central part of the loads was made from agar-agar and represented a deuterated polyethylene cylinder with small density 50 and 75 mg/sm3 and 1–2 mm diameter. On the ICT images, obtained in optical and soft X-ray range of a spectrum with 3–5 ns exposition, it is visible that on the axis of the polyethylene cylinder at the current`s rise time a cord is formed and it is separated into bright formations. They were observed on a background of a luminous area which occupied the initial neck volume. On time-integrated pinhole pictures obtained in SXR range (E > 1–4 keV), hot points with minimal size of 50 microns were registered. From the chronograms results, obtained by means of the optical high-speed-streak camera mount along the neck axis with time resolution 1 keV with short duration of 2–4 ns. Simultaneously with X-ray radiation neutrons with the maximal yield of 4.5×109 were registered. The average energy measured in 4 directions under angles with an axis of: 0○ (above the anode), 90○, 180○ (under the cathode) and 270○, were accordingly: 2.4±0.2, 2.5±0.1, 2.5±0.1, 2.5±0.1 MeV

Physics Of ICF Related Multiwire Array Implosion

At the present time an investigation into the process of current-driven implosion of cylindrical tungsten wire arrays is under way as applied to the ICF research The investigations performed at the Angara-5-1 facility have shown that after first several nanoseconds of current flowing plasma is generated on the surface of a wire and the current from the wire is switched to the plasma corona. The system includes low density plasma and a dense core. The core keeps its initial position for a significant period of the liner pulse duration and serves as a stationary plasma source. The plasma being continuously generated is accelerated to the liner axis by Ampere's force. This plasma is considerably thick and transfers some fraction of the current. For a better understanding of physics of the wire array implosion process of great interest are investigations into the spatial mass and current distributions inside the array during this process. The current work deals with these investigations performed at the Angara-5-1 facility and presented in three sections: current distribution inside the array during implosion, plasma density distribution during implosion using a method of X-ray probing, electron density distribution during stagnation using a laser interferometer