Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

This review of the potential of robust plasma facing components (PFCs) with liquid surfaces for applications in future D/T fusion device summarizes the critical issues for liquid surfaces and research being done worldwide in confinement facilities, and supporting R&D in plasma surface interactions. In the paper are a set of questions and related criteria by which we will judge the progress and readiness of liquid surface PFCs. Part-II (separate paper) will cover R&D on the technology-oriented aspects of liquid surfaces including the liquid surfaces as integrated first walls in tritium breeding blankets, tritium retention and recovery, and safety.

Liquid surfaces for fusion plasma facing components—A critical review. Part I: Physics and PSI

Applying liquid metals as plasma facing components for fusion power-exhaust can potentially ameliorate lifetime issues as well as limitations to the maximum allowed surface heat loads by allowing for a more direct contact with the coolant. The material choice has so far been focused on lithium (Li), as it showed beneficial impact on plasma operation. Here materials such as tin (Sn), gallium (Ga) and aluminum (Al) are discussed as alternatives potentially allowing higher operating temperatures without strong evaporation. Power loads of up to 25 MW m−2 for a Sn/W component can be envisioned based on calculations and modeling. Reaching a higher operating temperature due to material re-deposition will be discussed. Liquids typically face stability issues due to j × B forces, potential pressure and magnetohydrodynamic driven instabilities. The capillary porous system is used for stabilization by a mesh (W and Mo) substrate and replenishment by means of capillary action.

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Liquid metals as alternative solution for the power exhaust of future fusion devices: status and perspective

Helium effects on tungsten under fusion-relevant plasma loading conditions

The experimentally measured erosion rate of surfaces exposed to energetic particle bombardment at an elevated temperature exceeds that predicted by a summation of the physical sputtering rate and the thermodynamic sublimation/evaporation rate. A model based on the creation of surface adatoms, due to the energetic projectile bombardment of surfaces, and their subsequent sublimation/evaporation is developed to explain the enhanced erosion. Molecular dynamics simulations of beryllium confirm that the experimentally measured evaporation energy is consistent with the binding energy of adatoms. Experimental data of temperature-dependent erosion from both solid (beryllium) and liquid (lithium) samples are in agreement with the radiation activated adatom sublimation model.

Particle-induced erosion of materials at elevated temperature

The design of a compact, high-efficiency, high-flux capable compact-accelerator fusion neutron generator (FNG) is discussed. FNG's can be used in a variety of industrial analysis applications to replace the use of radioisotopes which pose higher risks to both the end user and national security. High efficiency, long lifetime, and high power-handling capability are achieved though innovative target materials and ion source technology. The device can be scaled up for neutron radiography applications, or down for borehole analysis or other compact applications. Advanced technologies such as custom neutron output energy spectrum, pulsing, and associated particle imaging can be incorporated.

Long life high efficiency neutron generator

The lithium sputtering yield from lithium and tin-lithium surfaces in the liquid state under bombardment by low-energy, singly charged particles as a function of target temperature is measured by using the Ion-surface Interaction Experiment facility. Total erosion exceeds that expected from conventional collisional sputtering after accounting for lithium evaporation for temperatures between 200 and $400\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$. Lithium surfaces treated with high-fluence D atoms are bombarded by ${\mathrm{H}}^{+}$, ${\mathrm{D}}^{+}$, ${\mathrm{He}}^{+}$, and ${\mathrm{Li}}^{+}$ at energies between 200 and $1000\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ and 45\ifmmode^\circ\else\textdegree\fi{} incidence. Erosion measurements account for temperature-dependent evaporation. For example, $700\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ ${\mathrm{He}}^{+}$ particles bombarding the D-treated liquid Li surface at room temperature result in a sputter yield of 0.12 Li/ion and at temperatures $\ensuremath{\sim}2.0{T}_{m}$ (where ${T}_{m}$ is the melting temperature of the sample), a yield near and above unity. The enhancement of lithium sputtering is observed to be a strong function of temperature and moderately on particle energy. Bombardment of a low-vapor-pressure lithium alloy (0.8 Sn-Li), used for comparison, also results in nonlinear rise of lithium erosion as a function of temperature. Measurements on both pure liquid Li and the alloy indicate a weak dependence with surface temperature of the secondary ion-induced secondary ion emission. Treatment of liquid Li surfaces with D, yields reduced sputtering under ${\mathrm{He}}^{+}$ impact by a factor of 5--6 when measured at room temperature due to preferential sputtering effects.

/pdf/collisional-and-thermal-effects-on-liquid-lithium-sputtering-4vu4j0tkgk.pdf

Collisional and thermal effects on liquid lithium sputtering

Temperature dependence of liquid-lithium sputtering from oblique 700 eV He ions

http://publish.illinois.edu/plasma-material-interactions/files/2015/04/2004-Coventry-Allain-Ruzic.pdf

Temperature dependence of liquid Sn sputtering by low-energy He + and D + bombardment

Aspects of the invention relate to several methods to deposit and regenerate target materials in neutron generators and similar nuclear reaction devices. In situ deposition and regeneration of a target material reduces tube degradation of the nuclear reaction device and covers impurities on the surface of the target material at the target location. Further aspects of the invention include a method of designing a target to generate neutrons at a high efficiency rate and at a selected neutron energy from a neutron energy spectrum.

M.D. Coventry

Papers

Long life high efficiency neutron generator

Collisional and thermal effects on liquid lithium sputtering

Temperature dependence of liquid-lithium sputtering from oblique 700 eV He ions

Temperature dependence of liquid Sn sputtering by low-energy He + and D + bombardment

Method and system for in situ depositon and regeneration of high efficiency target materials for long life nuclear reaction devices