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Nuclear reactions produce ten million times more energy than the chemical reactions e.g. from burning carbon, but the equilibrium thermal pressures for chemical reactions need temperatures of hundred °C while nuclear burns need many dozens of million °C. This is on the level for ITER or at NIF with using nanosecond laser pulses. In contrast, non-thermal pressures can be higher by lasers using nonlinear forces of picoseconds or shorter duration as computer results of 1978 had demonstrated by non-thermal plasma-block acceleration. This is in full agreement with the ultrahigh acceleration measured by Sauerbrey since 1996 thanks to his use of ultra-extreme powers of picosecond CPA-laser pulses. Even the very inefficient classical fusion of hydrogen with the 11B can be used for the non-thermal reaction with sufficiently modest heating in a reactor for generation electricity.

Evaluation of nuclear binding energies from theory close to available measurements of a very high number of superheavy elements (SHE) based on α-decay energies Q α , arrived at a closing shell with a significant neutron number 184. Within the option of several discussed magic numbers for protons of around 120, Bagge's numbers 126 and 184 fit well and are supported by the element generation measurements by low energy nuclear reactions (LENR) discovered in deuterium loaded host metals. These measurements were showing a Maruhn–Greiner maximum from fission of compound nuclei in an excited state with double magic numbers for mutual confirmation.

Protons and neutrons are emitted in many fusion processes of light nuclei. In a fusion reactor, a proton and a neutron thus generated may again fuse with each other. Or they can in turn fuse with or be captured by an un-reacted nuclear fuel, for example deuterium. The average center-of-mass energy for such reaction is around 10 keV in a typical fusion reactor. At this low energy, the reacting nucleons are in an s-wave state in terms of their relative angular momentum. The single-gamma radiation process is thus strongly suppressed due to conservation laws. Instead the gamma ray released is likely to be accompanied by soft X-ray photons from a nuclear bremsstrahlung process. The generated soft X-ray has a continuous spectrum and peaks around a few hundred eV to a few keV. The average photon energy and spectrum properties of such a process are calculated with a semi-classical approach, with the explicit example of proton–neutron capture. This phenomenon may have been observed in some prior tokamak discharge experiments, and its interpretation is complicated by the presence of electron bremsstrahlung. However, it also opens up the possibility of new plasma diagnostics which are more sensitive to the ionic or nuclear degree of freedom.

The performance and characteristics of direct sodium-borohydride/hydrogen-peroxide (NaBH 4 /H 2 O 2 ) fuel cells are studied in the context of potential applications for air independent propulsion for outer space and underwater. Due to the existence of ocean (sea) water as a natural heat sink, this new fuel cell technology is best suited for underwater propulsion/power systems for small scale high performance marine vehicles. The characteristics of such a power system are compared to other options, specifically for the underwater scenario. The potential of this fuel cell is demonstrated in laboratory experiments. Power density over 1.5 W cm −2 , at 65 °C and ambient pressure, have been achieved with the help of some unique treatments of the fuel cell. One such treatment is an in-situ electroplating technique, which results in electrodes with power density 20–40% higher, than that of the electrodes produced by the ordinary ex-situ electroplating method. This unique process also makes repair or reconditioning of the fuel cell possible and convenient.

When a fuel cell (FC) utilizes liquid fuels directly, a few complications arise due to the conductance or the potential conductance of the fuel. Fuel cell stacks are typically designed in a bipolar fashion so that the voltage of individual cells can be added up in series to give an adequate and convenient output voltage. The conductivity of fuels brings about two risks if the bipolar stack is not properly designed and engineered. On one hand, the conductive liquid fuel may short circuit the neighboring cells of a bipolar FC stack with traditional integrated fuel manifolds. On the other hand, the conductive fuel may pass a high voltage to some parts of the cell through an ordinary manifold, causing excessive corrosion. These issues need to be addressed through a cell-isolation fuel distribution network (FDN). The function of such an FDN is to increase the shunting resistance of neighboring cells, so as to maintain a reasonable open circuit voltage. Also, the presence of a gas phase in the liquid fuel during cell operation affects fuel circulation and therefore needs to be considered in the FDN design. On the plus side, a liquid fuel, in contact with high surface area FC electrodes, functions as a super-capacitor, giving the FC an excellent pulse overload capacity. Also the fuel itself is a fair coolant, enabling high power density at minimal increase in stack weight. These considerations are applied to a kilowatt NaBH4/H2O2 fuel cell stack to generate the desired operational characteristics.

A model has been designed and constructed for the all-liquid, sodium borohydride/hydrogen peroxide fuel cell under development at the University of Illinois at Urbana-Champaign. The electrochemical behavior, momentum balance, and mass balance effects within the fuel cell are modeled using the Butler–Volmer equations, Darcy's law, and Fick's law, respectively, within a finite element modeling platform. The simulations performed with the model indicate that an optimal physical design of the fuel cell's flow channel land area or current collector exists when considering the pressure differential between channels, and the diffusion layer permeability and conductivity. If properties of the diffusion layer are known, the model is an effective method of improving the fuel cell design in order to achieve higher power density.

Catalyst selection, deposition method and substrate material selection are essential aspects for the design of efficient electrodes for fuel cells. Research is described to identify a potential catalyst for hydrogen peroxide reduction, an effective catalyst deposition method, and supporting material for a direct borohydride/hydrogen peroxide fuel cell. Several conclusions are reached. Using Pourbaix diagrams to guide experimental testing, gold is identified as an effective catalyst which minimizes gas evolution of hydrogen peroxide while providing high power density. Activated carbon cloth which features high surface area and high microporosity is found to be well suited for the supporting material for catalyst deposition. Electrodeposition and plasma sputtering deposition methods are compared to conventional techniques for depositing gold on diffusion layers. Both methods provide much higher power densities than the conventional method. The sputtering method however allows a much lower catalyst loading and well-dispersed deposits of nanoscale particles. Using these techniques, a peak power density of 680 mW cm−2 is achieved at 60 °C with a direct borohydride/hydrogen peroxide fuel cell which employs palladium as the anode catalyst and gold as the cathode catalyst.

A fuel cell (FC) using liquid fuel and oxidizer is under investigation. H2O2 is used in this FC directly at the cathode. Either of two types of reactant, namely a gas-phase hydrogen or an aqueous NaBH4 solution, are utilized as fuel at the anode. Experiments demonstrate that the direct utilization of H2O2 and NaBH4 at the electrodes results in >30% higher voltage output compared to the ordinary H2/O2 FC. Further, the use of this combination of all liquid fuels, provides numerous advantages (ease of storage, reduced pumping requirements, simplified heat removal, etc.) from an operational point of view. This design is inherently compact compared to other cells that use gas phase reactants. Further, regeneration is possible using an electrical input, e.g. from power lines or a solar panel. While the peroxide-based FC is ideally suited for applications such as space power where air is not available and a high energy density fuel is essential, other distributed and mobile power uses are of interest.

One key issue in heavy ion beam fusion (HIBF) is how to effectively focus high-current and high-perveance ion beams onto a small target area. Space charge neutralization is needed to prevent defocusing as the ion density compresses during focusing. The present study is concerned with the physics of space-charge neutralization by use of various concepts for injection of electrons into the ion beam in addition to plasma neutralization. To date the most widely studied approaches to neutralization use a preformed plasma or ionize a background gas in the beam line. However, these schemes alone face difficulties due to local non-uniformities in charge neutralization due to beam dynamic/focusing effects. Thus, two supplemental techniques are under study and will be discussed here. One involves axially injection of electrons created in a thin foil in the beam path. The other uses a magnetic field to guide the electrons into the direction of the beam path. Both techniques would be used in combination with conventional background plasma, providing added control of neutralization.

Electronic structure modeling is carried out for bulk Pd–H system with implications for certain surface effects and hydrogen transport. The calculation is performed under the framework of density functional theory. The results provide new insight into the charge state of H inside Pd. The H is slightly negatively charged over the composition range studied, and the negative charge around the proton increases with an increasing loading of hydrogen. By studying the behavior of H at the “bridging” site, which is important to surface and transport phenomena, this paper helps to explain why the effective charge observed in H drift experiments is different from the static charge state.

The powerful radio galaxy PKS 1138−262 is a massive galaxy in a dense environment as indicated by optical, NIR, radio and X-ray observations. We have found an overdensity of Ly α emitters within 1.5 Mpc of the radio galaxy which form a proto cluster at z =2.2. We have also found numerous candidate H α emitters near 1138−262. The surface density of H α candidates increases towards the radio galaxy, contrary to the density of Ly α candidates. We have spectroscopically confirmed the identification of nine H α candidates whose velocity dispersion is smaller than for the Ly α emitting sample. The field of 1138−262 also contains a high density of EROs and X-ray emitters. We will discuss the implications of these measurements and show that there are several galaxy populations present in the proto cluster.

A bounce-averaged Fokker–Planck code (BAFP) has been developed and tested. BAFP implements a multi-dimensional, energy-conservative, time-implicit solution of the Fokker–Planck equation in two velocity and one spatial dimensions. A Jacobian-free, Newton–Krylov solver efficiently inverts the time-implicit equations. Bounce averaging removes the fast time scale for motion of trapped ions, so low-collisionality ion systems can effectively be treated. BAFP has been applied to ion dynamics in virtual-cathode spherical inertial electrostatic (IEC) fusion devices, which employ a spherical cloud of electrons to create a kV electrostatic well to confine and spherically focus ions. Here, Penning-type IEC devices are studied. Steady-state ion distribution functions obtained with BAFP in operating limits of interest are presented, and show that a variety of steady-state equilibriums are possible in these systems.

Based on research at the University of Illinois, a commercial neutron source has been developed by Daimler Chrysler Aerospace using a small grided-type Inertial Electrostatic Confinement (IEC) plasma device (Miley and Sved, 1997) This device employs a unique "Star-Mode" deuterium plasma discharge to create ion-beam driven fusion reactions in a plasma target (Miley et al., 1997a, 1997b, 1997c; Miley, 1999). As such, it represents the first commercial application of a confined fusing plasma. The Star-Mode discharge is an essential feature of this device since it minimizes ion-grid collisions and also allows tight beam focussing.

Two prior D-3He field-reversed configuration (FRC) reactor designs, ARTEMIS and SAFFIRE are reviewed to identify key physics, technology, and design issues for FRC development. It is concluded that the D-3He FRC can potentially offer a cost competitive and environmentally compatible power plant if the technology issues can be suitably resolved. The D-3He FRC also appears to be particularly attractive for non-electrical application such as 3He breeding or hydrogen production. An important developmental issue becomes whether or not a D-T version should be employed as the first-generation unit. If so, emphasis must be placed on methods to handle high neutron and heat first-wall loadings, e.g. by use of a liquid first wall. Also, the development of improved thermal energy conversion cycles such as the use of liquid metal MHD becomes an important goal.

Energy-conservative implicit integration schemes for the Fokker-Planck transport equation in multidimensional geometries require inverting a dense, non-symmetric matrix (Jacobian), which is very expensive to store and solve using standard solvers. However, these limitations can be overcome with Newton-Krylov iterative techniques, since they can be implemented Jacobian-free (the Jacobian matrix from Newton's algorithm is never formed nor stored to proceed with the iteration), and their convergence can be accelerated by preconditioning the original problem. In this document, the efficient numerical implementation of an implicit energy-conservative scheme for multidimensional Fokker-Planck problems using multigrid-preconditioned Krylov methods is discussed. Results show that multigrid preconditioning is very effective in speeding convergence and decreasing CPU requirements, particularly in fine meshes. The solver is demonstrated on grids up to 128 x 128 points in a 2D cylindrical velocity space ({upsilon}{sub r}, {upsilon}{sub p}) with implicit time steps of the order of the collisional time scale of the problem, {tau}. The method preserves particles exactly, and energy conservation is improved over alternative approaches, particularly in coarse meshes. Typical errors in the total energy over a time period of 10{tau} remain below a percent.

Anomalous interaction of terawatt-picosecond laser pulses allows side-on ignition of solid state density fusion fuel with the unexpected possibility of igniting uncompressed hydrogen–boron p11 B. Suppression of relativistic self-focusing by using very clean laser pulses with an extremely high contrast ratio is essential to achieve ignition thresholds only ten times more difficult than fusion of deuterium–tritium (DT). This opens the possibility for laser driven fusion energy without neutrons and less radioactivity than from burning coal. The complex nonlinear optical properties involved are elaborated.

The scaling of neutron generation versus ion current is important in evaluating the prospect of an inertial electrostatic confinement (IEC) as a neutron source. In this paper, the scaling of neutron generation versus ion current, I , based on the results of both the experiments and the numerical simulations is discussed. The experiments shows the scaling of I 2 , while the numerical simulation gives the stronger scaling of I 3 . The regime of current in the present experiments is limited by the capability of the available power supplies. As the current increases, the potential structure is numerically shown to be more unstable. The intermittent peaking of the density is accompanied with unstable potential behaviors and brings about the higher density in time averaging. This may be a reason why the numerical simulation gives a stronger scaling versus ion current. Experiments in higher ion current regime may be required to verify the scaling estimated by the numerical simulation.

In the inertial electrostatic confinement (IEC) device, deuteron ions are accelerated, producing fusion reactions as they react with a deuterium plasma target. Present devices offer 106–107 2.5 MeV D-D n s−1 during steady-state operation. Higher yield pulsed versions are under development. Consequently the IEC neutron source is currently competitive, in terms of neutron strength, with Cf-252 and accelerator solid-target sources and offers a number of advantages, including an on-off capability, longer lifetime without deterioration in strength, and minimum involvement of radioactivity. These features simplify IEC usage and ease licensing restrictions. Conversion to higher energy (14 MeV) neutrons by substituting D-T fill gas for pure deuterium fill gas has confirmed the higher source strength of 108–109 D-T n s−1 for the same IEC unit size. For these reasons, the IEC provides an excellent research laboratory neutron source as well as long life, a low maintenance cost industrial source for neutron activation analysis and non-destructive testing. Two basic geometries have been developed—a spherical unit and a cylindrical unit. Spherical units have vacuum vessel diameters ranging from 15 cm to 60 cm. Present cylindrical units are approximately 12 cm in diameter and 1 m long, but smaller designs are under development. The two geometries are complementary: the spherical unit provides a ‘point’ source of neutrons, while the cylindrical device provides a ‘line’ source.

The non-self-adjoint Frieman?Rotenberg equation for the linear ideal magnetohydrodynamic modes in flow equilibria is numerically solved in shaped finite-aspect ratio axisymmetric tokamak geometry. A quadratic form is derived from this equation, and, in particular, the self-adjoint force operator with finite toroidal rotation is cast into a manifestly self-adjoint form. The toroidal rotational velocities in the subsonic regime are considered. The quadratic form is discretized by a mixed finite-element procedure in the radial direction and by Fourier modes in the periodic directions. The mode frequency of the unstable mode is located by root searching, and the final root refinement is obtained by a rapid inverse iteration procedure for complex roots. The real part of then= 1 internal kink mode scales linearly with the plasma rotation, and the imaginary part of the unstable mode is at least an order of magnitude higher in the presence of high plasma rotation velocities. The kink mode is also found to be unstable at high rotation velocities, even when the axis safety factor is above unity. The instability characterized by these features is termed here as the “centrifugal” instability. The centrifugal kink instability would have finite real parts, as shown by the plasma rotation observed in plasma devices such as tokamaks. To explain the features of this mode, the plasma rotation should be taken into account. Therein lies the usefulness of the computational analysis presented here.

Based on the few reliable and reproducible cold fusion experiments, the power law of reaction probability on nuclear distance arrived at a value of 3 pm which is in agreement with results derived by a different method (Vigier and Rambaut) of 2.5 pm. For our plasma and swimming electron model we calculate a screening factor of 14.

Radioluminescence experiments have been performed on single- and polycrystal CsI at the pulsed TRIGA nuclear reactor of the University of Illinois. 95% of the 100 krad dose (SiO 2 ) was contributed by gamma-rays, the rest by neutrons. The radioluminescence was measured in the near infrared (up to 5.5 μm) and in the visible range. At the peak of the radiation pulse (dose rate of 6.9 Mrad/s), single-crystal CsI emits ∼ 40 mW/cm 2 in the infrared, against virtually nothing for the polycrystal CsI. In the visible range, however, the emission intensity is much larger, ranging from 300 mW/cm 2 for the polycrystal CsI to more than 5 W/cm 2 for the single-crystal CsI. It was also found that dose accumulation by consecutive pulsing causes the luminescence to decrease. The rate of decrease depends on the sample, on the proportion of thallium as a dopant and on the wavelength range considered. Increasing the temperature of CsI also causes a decrease in radioluminescence and repairs the damage to the crystal by annealing the quenching centers, essentially allowing full recovery of the radioluminescence intensity.

The authors have developed an energy conversion concept, called Photon-Intermediate Direct Energy Conversion (PIDEC), that makes possible a two-step conversion of high grade nuclear energy (fission or fusion) to electricity or other useful high grade energy forms without intermediate thermalization. In PIDEC the nuclear fuel has a low average density, with local scale lengths significantly shorter than the range of the energetic nuclear reaction products. In the first step of the process, the nuclear energetic reaction product energy is transported to a fluorescer gas which converts it into photons. Then, in the second step of the process, the photons are transported out of the nuclear reactor to a medium which converts the photon energy to the desired product high grade energy form, such as electricity. We calculate that electricity can be produced, non-thermally, with an efficiency of up to 30%. With the addition of intermediate and bottoming thermal cycles, efficiency for electricity production could be as high as 70%, double that of conventional nuclear power plants. In addition to electric power, photolysis makes other product forms possible. These products include useful feedstock, or combustion chemicals, such as hydrogen and carbon monoxide, and excited molecular and atomic states, used for laser amplifiers or oscillators.

The incident velocity distribution of high-energy alpha particles bombarding the first wall of an axisymmetric tokamak is evaluated as a function of poloidal angle (γ). The resulting helium concentration profile as a function of the poloidal angle and the implant depth is calculated for a typical Experimental Power Reactor (EPR) design. The critical helium concentration for blistering is first exceeded at θ ~55°. Peak concentrations are reduced somewhat through continuous D-T sputtering which, dependent on θ, reduces the blister skin thicknesses. The blistering-induced impurity level is found to increase drastically (≲

The importance of using non D-T fusion fuels is briefly reviewed. D-D operation where product 3He and T are burned at the same rate as produced (called “catalyzed-D”) is identified as the only advanced fuel that avoids breeding of fuels and yet potentially offers operation under conditions achievable by present magnetic confinement devices. The conceptual design of a Tokamak reactor using catalyzed-D indicates a relatively large reactor (∼12 GW gross output, 12 m radius torus), but this could still be quite attractive due to potential improvements in efficiency, reduced radioactivity inventory, and increased first-wall life-time. While a number of uncertainties remain, the feasibility of such a reactor does not appear to be too great an extension beyond D-T reactors. Although a fuel such as p-11B could offer further advantages by essentially eliminating neutrons and tritium, suitable methods of confining and burning it require a much larger extrapolation of current experience.

The potential of using advanced-fuel heavy-ion beam fusion is discussed as an avenue for achieving improved environmental and safety factors in a fusio

Terrestrial resources of 3He are too limited to support a significant D-3He power program. In the present paper, two other possible near-term 3He sources are briefly reviewed: breeding and lunar mining. Two prime approaches to breeding are considered, namely, semicatalyzed D-breeder/D-3He satellite systems and plants operating on the DD-3He cycle. Lunar mining is viewed as a possible alternative to breeding for near-term terrestrial plants, but a major contributor to long-term uses of fusion power for space exploration.

Aspects of both vacuum breakdown and unipolar arcs of importance to CTR devices are discussed. A design correlation for vacuum breakdown is presented for three regimes related to surface treatment: initial, field-emission, and ultimate. For the initial regime, the breakdown voltage V b and equivalent spacing y are related by V b (volt) ∼48.8 y 1 2 (cm). Extensive surface treatment allows voltages ∼6 × higher, but long-term maintenance of surface conditions is difficult. Unipolar arc formation at the sheath of a plasma-wall interface could lead to erosion rates equivalent to ∼10 sputtered atoms per bombarding ion, several orders of magnitude larger than for normal ion sputtering. Suppression of arcing by area subdivision or by insulating coatings is discussed.

Inertial confinement fusion (ICF) concepts, as compared to magnetic confinement, provide an attractive approach to burning “advanced-fusion fuels” to achieve fusion. A key advantage of the ICF approach is that the absence of externally imposed magnetic fields avoids large cyclotron radiation losses. An important advantage of advanced-fusion fuels is that advanced fuels provide “cleanliness” due to less neutron production and tritium handling. Present studies focus on the A-FLINT ( A dvanced- F uel L ayered I gnitor/Pellet N urturing T ritium) design which consists of a D-T fueled seed surrounded by a D-layer and appropriate tamper. A heavy-ion beam accelerator is proposed to provide adequate input-energy and efficiency. The pellet design minimizes input requirements through shock ignition of the small D-T core, providing a matchhead effect. The surrounding layers provide unburned tritium to fuel subsequent pellets, eliminating the need for a lithium blanket and simplifying the reaction vessel design.

This panel discusses the National Academy of Science — Air Force Studies Board preliminary report entitled Advanced Fusion Power .

Fusion-product transport, from an axisymmetric tokamak plasma to the first wall, is modelled. Prompt-loss profiles (i.e. prior to slowing) are calculated as a function of poloidal angle. There is a significant flux incident at near-grazing angles, thus enhancing sputtering. Non-prompt losses are also obtained; the resulting wall bombardment is ≲110 of the prompt contribution but is localized at the outboard edge of the tokamak. To verify fusion-product transport, a detection experiment has been proposed and modelled for a device like PLT or TFTR. Blistering is the dominant wall erosion mechanism. Serious impurity contamination of the plasma can result: Δ〈Z〉eff/s ~ 6.5 in a TFTR-size device, and 0.014 in UWMAK-I; this poses a potential limit on reaction burn time. These effects can be minimized by: 1) periodic B-field reversal, 2) special wall materials and/or rapid wall replacement designs in peak flux areas, 3) increased plasma-wall separation, and 4) increased plasma current.

There are two major electrostatic direct energy converter concepts which will be discussed from the point of view of the surfaces. One is the Venetian blind concept and the other is the periodic electrostatic focusing concept. They are both of the direct collector type. Fluxes of D+, T+, He++, electrons, and X-rays are given. Design consideration due to thermionic emission, secondary electron emission, and radiation cooling are discussed. A detailed discussion is devoted to breakdown physics, the voltages and electric field strengths that can be employed, and how surface deterioration may affect voltage holding due to He++ bombardment blistering.

Transmission electron microscopy has been used to investigate the effect of total dose on the depth distribution of cavities (voids or bubbles) in nickel irradiated at 500°C with 500-keV 4He+ ions. A transverse sectioning technique, which allows one to obtain the entire depth distribution of cavities and of damage from a single specimen, was utilized. The size, number density and volume fraction of bubbles or voids were measured from the micrographs taken from samples sectioned parallel to the direction of the incident beam. The results for the dose range studied (2 × 1019 to 1 × 1021ions/m2) show that the average cavity diameter, number density, and the volume fraction (i.e. swelling) increases with increasing dose. The peak in the swelling distribution occurs at depths 8 to 15% deeper than the peak in the calculated projected range profile.

The potential importance of direct energy conversion to the long-term development of fusion power is discussed with emphasis on the possibility of alleviating waste heat problems. This is envisioned to be important for any central power station in the 21st century and crucial for future space applications. Various novel conversion methods are briefly considered, including direct collection, magnetic expansion, synchroton radiation conversion, and nonthermal neutron energy conversion methods. Due to the intimate connection between the type of fusion fuel, the confinement scheme, and the energy conversion technique, all three elements must be optimized simultaneously for high overall efficiency.

Studies under the University of Illinois PROMETHEUS (Plasma Reactor Optimized for Materials Experimentation for Thermonuclear Energy Usage) project are described that started in 1971 with the realization that a practical fusion-plasma neutron source was feasible with a net-power input (rather than production). The basic objectives were similar to those in later FERF (Fusion Engineering Research Facility) studies: namely, to maximize the neutron flux and usable experimental volume; to include the flexibility to handle a variety of both materials and engineering experiments; to minimize capital and operating costs; and to utilize near-term technology. The PROMETHEUS design provides a neutron flux of ∼5 × 1014 n/cm2 s by injection of ∼30 MW of neutral-beams into a 20 cm radius mirror-confined plasma. Charge-exchange bombardment of the first wall is viewed as a key problem in the design and is discussed in some detail. To gain yet higher neutron fluxes for accelerated testing, two alternate designs have ben studied: a “Twin-beam” injection device and a field reversed mirror concept. The latter potentially offers fluxes approaching 1016 n/cm2 s but involves more speculative technology.

The reduced neutron flux and lower average energy characteristic of the Cat-D fusion cycle, compared to D-T, result in reduced first-wall damage. In order to compare first-wall lifetime expectations, neutron-induced damage and also surface erosion due to sputtering are evaluated for recent conceptual tokamak reactor designs employing Cat-D and D-T fuels. While neutron damage appears to limit the D-T first wall to ~7 years lifetime, the Cat-D wall is found to last 20 years or longer. While sputtering erosion is more severe for Cat-D, this does not appear restrictive with use of appropriate first-wall coating techniques.

Many existing energy related technologies have developed under the influence of social, economic, or state of the art constraints, and they cannot be viewed as optimum systems according to the second law of thermodynamics. Controlled fusion research presents an opportunity to optimize a nascent technology with respect to second law considerations in order to develop a practical energy source. In its present state of development, fusion research offers several independent approaches that may result in a net power producing fusion reactor. This paper discusses how second law considerations might be used to narrow the range of choices that must be made among various fusion fuel cycles. From a second law point of view, the most desirable fusion reactors are those for which the energy of charged particles can be converted directly into d.c. electrical power, while still allowing the energy that could be recovered by an efficient high-temperature “blanket” to be transported largely by radiation. Fusion research in all major industrialized countries is developing the deuterium-tritium (D-T) fuel cycle for first-generation fusion power plants. It will be shown that other fuel cycles have significant advantages over the D-T fuel cycle according to second law principles.

As suprathermal fusion products slow down in a tokamak, their average drift is inward. The effect on the alpha heating and thermalization profiles is examined. In smaller TFTR-type devices, heating in the outer region can be cut in half. Also, the fusion-product energy-distribution develops a positive slope, representing a possible driving mechanism for microinstabilities. Another instability that can seriously affect outer plasma conditions, shear Alfven transport of alphas, is also considered.

1. 1. The study of the clinical effects of ultraviolet blood irradiation in 445 consecutive and unselected cases of acute pyogenic infections has been made. Confirmation of our original preliminary findings was observed. These findings showed that ultraviolet blood irradiation therapy was a rapid, efficient and non-specific control of all types of acute pyogenic infections (except bacterial endocarditis), the use of which was characterized by a quick subsidence of toxic symptoms, a disappearance of bacterial proliferation and invasion and an uneventful convalescence. 2. 2. In seventy-four consecutive and unselected cases of virus or virus-like infections we have observed results comparable to the favorable effects observed in its use in acute pyogenic infections. 3. 3. It was found that sulfa sensitive infections are easily and favorably influenced by ultraviolet blood irradiation therapy and that a large variety of infections not controlled by sulfa drugs can be rapidly and efficiently controlled by ultraviolet blood irradiation therapy. 4. 4. Many penicillin-resistant infections respond favorably to ultraviolet blood irradiation therapy, both the acute pyogenic types and the virus or virus-like infections. 5. 5. We were able to confirm the preoperative protective effect of ultraviolet blood irradiation therapy described by Rebbeck and fittingly called the Rebbeck Effect. 6. 6. There is no contraindication to the joint use of penicillin and ultraviolet blood irradiation therapy, but sulfa drugs cannot be safely used in the first four or five days following ultraviolet blood irradiation therapy.