A5010828031- Nuclear reactor physics and engineering
- Nuclear Engineering Thermal-Hydraulics
- High-pressure geophysics and materials
- Nuclear Materials and Properties
- Advanced Surface Polishing Techniques
- Nuclear and radioactivity studies
- Advanced machining processes and optimization
- Graphite, nuclear technology, radiation studies
- Diamond and Carbon-based Materials Research
- Rare-earth and actinide compounds
- X-ray Diffraction in Crystallography
- Crystal Structures and Properties
- Advanced Chemical Physics Studies
- Metallurgy and Material Forming
- Laser-Plasma Interactions and Diagnostics
- Risk and Safety Analysis
- Organometallic Compounds Synthesis and Characterization
- High-Velocity Impact and Material Behavior
- Boron and Carbon Nanomaterials Research
- Electromagnetic Launch and Propulsion Technology
- Metal Alloys Wear and Properties
- Superconductivity in MgB2 and Alloys
- Force Microscopy Techniques and Applications
- Crystallography and molecular interactions
- Electron and X-Ray Spectroscopy Techniques
University of Rostock
2022-2025
University of Edinburgh
2003-2022
Los Alamos National Laboratory
1979-1989
Research Applications (United States)
1989
UNSW Sydney
1969-1988
Rockwell Automation (United States)
1979
Los Alamos Medical Center
1979
MACOM (United States)
1979
University of Oxford
1973
The University of Texas at Austin
1970
Temperature distributions for typical cases of orthogonal machining with a continuous chip were obtained numerically by solving the steady two-dimensional energy equation using finite element method. The distribution heat sources in both primary and secondary zones was calculated from strain-rate flow stress distributions. Strain, velocity deformed grid patterns quick-stop experiments. Flow considered as function strain, temperature. chip, workpiece tool (actual shape size) treated one...
Experiments are described in which an explosive quick-stop device and printed grids (0.002 square) were used to measure the deformation (streamlines of flow) zone intense shear removed chip is formed orthogonal machining. A method given for calculating strain-rate from experimental streamlines it shown that both maximum mean values this directly proportional speed (shear velocity) inversely scale (depth cut).
Extreme conditions inside ice giants such as Uranus and Neptune can result in peculiar chemistry structural transitions, e.g., the precipitation of diamonds or superionic water, so far experimentally observed only for pure C─H H 2 O systems, respectively. Here, we investigate a stoichiometric mixture C by shock-compressing polyethylene terephthalate (PET) plastics performing situ x-ray probing. We observe diamond formation at pressures between 72 ± 7 125 13 GPa temperatures ranging from...
Results obtained from machining and conventional slow-speed compression tests are used to calculate the constants σ 1 n in empirical stress/strain equation = *** e over a range of strain-rates (10 -3 2·8 times 10 4 /s) temperatures (room temperature 200°C) for low carbon, free steel. The results consistent with those similar material using high-speed tension tests. Some showing influence higher (up 800°C) on flow stress also by considering along tool-chip interface. These show dynamic...
The finite element program developed in previous work [1] for calculating the temperature distributions chip and tool metal machining has been extended its range of application. Specifically, no longer needs a flow field as input it can accommodate wide shear angle contact lengths. An important feature this paper is that fields from method have compared with temperatures obtained previously described metallographic [7]. This first time these two techniques used same conditions comparisons...
Angle-dispersive x-ray powder diffraction experiments have been performed on yttrium metal up to 183 GPa. We find that the recently discovered $oF16$ structure observed in high-$Z$ trivalent lanthanides is also adopted by above 106 GPa, pressures where it has a superconducting temperature of $\ensuremath{\sim}20$ K. refined both tetragonal and rhombohedral structures against data from preceding ``distorted-fcc'' phase we are unable state categorically which these true this phase. Finally,...
Abstract Carbon has a central role in biology and organic chemistry, its solid allotropes provide the basis of much our modern technology 1 . However, liquid form carbon remains nearly uncharted 2 , structure most physical properties are essentially unknown 3 But is relevant for modelling planetary interiors 4,5 atmospheres white dwarfs 6 as an intermediate state synthesis advanced materials 7,8 inertial confinement fusion implosions 9 hypervelocity impact events on 10 general understanding...
Abstract The effect of hyperthermia (42°C) on K + transport has been examined by monitoring the uptake 42 KCl Chinese hamster (line CHO) cells at both 37° and 42°C as well 37°C following a 30‐min treatment 42°C. Early studies showed that CHO exhibit two components Consequently, it was necessary to determine rate equations describing three‐compartment system (i.e., bathing medium cell‐associated compartments) apply them this system. Using behavior tracer in each compartment general solutions...
Abstract Laser-driven dynamic compression experiments of plastic materials have found surprisingly fast formation nanodiamonds (ND) via X-ray probing. This mechanism is relevant for planetary models, but could also open efficient synthesis routes tailored NDs. We investigate the release mechanics compressed NDs by molecular dynamics simulation isotropic expansion finite size diamond from different P - T states. Analysing structural integrity along paths simulations, we substantial...
$I\phantom{\rule{0}{0ex}}n$ $s\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}u$ x-ray diffraction of shock-compressed plastics suggests the formation liquid metallic hydrogen via carbon-hydrogen phase separation.
A theory is given for calculating chip geometry, cutting forces, etc., from fundamental work material properties and conditions. The flow stress of the (0·16 per cent carbon steel) used in analysis are taken high-speed compression test results. predicts main trends observed machining experiments a limited comparison with experimental results shows good quantitative agreement. possible explanation occurrence built-up edge, involving dynamic strain ageing (blue-brittleness) along tool-chip...
Severe local muscle fatigue may be a precursor of repetition strain injuries (RSI). In any event it produces discomfort and limits production. This is evaluated by analysing the amplitude frequency electromyographic signals extensor flexor muscles during repetitive wrist extension against constant torque. The absolute integral signal increased with angle but did not change exercise time period. suggests that analysis better for evaluation load, in evaluating fatigue. rate decrease centre was...
Many of the recent advances in optical lithography have been driven by utilization complex photomasks using proximity correction (OPC) or phase-shifting technologies. These masks are difficult and expensive to manufacture so ability test characterize mask making process is very important. This paper examines issues involved use relatively low-cost electrical critical dimension (ECD) measurement features. Modified cross-bridge structures designed allow on-mask dense isolated, binary...
Focused ion beam (FIB) systems are commonly used to image, repair and modify integrated circuits by cutting holes in passivation create vias or selectively break metal tracks. The can also be deposit a metal, such as platinum, new connections. These techniques very useful tools for debugging designs testing possible changes the circuit without expense of mask sets silicon. This paper presents test structures which characterize FIB induced platinum deposition process. Sheet resistance have...
Vanadium is reported to undergo a pressure-induced bcc-rhombohedral phase transition at 30--70 GPa, with pressure that sensitive the hydrostaticity of sample environment. However, experimental evidence for structure high-pressure being rhombohedral surprisingly weak. We have restudied vanadium under 154 GPa using both polycrystalline and single-crystal samples, variety different transmitting media (PTM). find only when samples does one observe phase; diffraction profiles from do not fit...
The insulator–metal transition in liquid hydrogen is an important phenomenon to understand the interiors of gas giants, such as Jupiter and Saturn, well physical chemical behavior materials at high pressures temperatures. Here, path toward experimental approach detailed based on spectrally resolved x-ray scattering, tailored observe characterize metallization dynamically compressed hydrocarbons regime carbon–hydrogen phase separation. With help time-dependent density functional theory...
X-ray powder diffraction experiments using resistively heated diamond anvil cells have been conducted in order to establish the phase behavior of antimony up 31 GPa and 835 K. The dip melting curve at 5.7 840 K is identified as triple point between Sb-I, incommensurate Sb-II, liquid phases. No evidence previously reported simple cubic was observed. Determination boundary Sb-II Sb-III suggests existence a second region 13 1200 composite structure found remain ordered highest temperatures...
Abstract Small-angle X-ray scattering (SAXS) has been widely used as a microstructure characterization technology. In this work, fully connected dense forward network is applied to inversely retrieve the mean particle size and distribution from SAXS data of samples dynamically compressed with high-power lasers probed free electron lasers. The trained allows automatic acquisition information, performing well in predictions on single-species nanoparticles theoretical model situ experimental...
The behavior and structure of Rb are explored up to 264 GPa, a pressure at which the density is increased more than eightfold. previously predicted double-hexagonal close packed stable above 200 while lower pressures change in compressibility 30 GPa arises from $s$-$d$ charge transfer. Above authors find that has regular compression $d$-type transition metal.