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国际医学放射学杂志 2015年第2期 198-199页

作者： m.m.Alakhras P.C.Brennan m.rickard R.Bourne C.mello-Thoms 高飞 medical Image Perception and Optimization Group(mIOPe G) Faculty of Health Sciences The University of SydneyRoom M221 75 East Street Sydney NSW 2141 Australia

摘要目的本研究旨在比较采用数字乳腺体层摄影(DBT)加数字钼靶摄影(Dm)和单独采用Dm诊断的效能,有DBT经验的放射医师的作用。方法本研究通过了伦理委员

关键词：放射医师 DBT 体层摄影乳腺乳房定位

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Chemistry : structure and dynamics / James N. Spencer, George m. Bodner, Lyman H. rickard.

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1999年

作者： James N. Spencer George m. Bodner Lyman H. rickard.

来源：畅想之星图书光盘版（南... 评论

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Delivery of inert gas through a vertical borehole using inert gas generator: A theoretical study

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International Journal of mining Science and Technology 2020年第4期30卷 501-510页

作者： rickard Hansen Sustainable minerals Institute The University of QueenslandBrisbaneQueensland 4072Australia

The delivery of the inert gas through a vertical borehole using inert gas generator or IGG is *** limitations and/or transient effects are *** the analysis,the borehole diameter,borehole length,type of borehole and partial condensation prior to entering the borehole were varied.A choked flow will occur for a contraction exit or borehole of 0.3 m in diameter if no condensation prior to the contraction *** partial condensation takes place,a borehole diameter of 0.3 m will be possible if almost 50%of the water vapour ***,pressure losses along boreholes with a diameter of 0.3 or 0.4 m are significant and could pose a challenge if trying to mitigate the pressure *** a booster fan prior to the inlet of the 0.4 m lined borehole would still be a *** corresponding case with a 0.5 m borehole presents much more favourable pressure *** 0.5 m diameter lined borehole should be regarded as the lower *** rapid heating of the unlined borehole surface will increase the risk of thermal spallation and possibly imposing *** the mechanisms during gas delivery will increase the likelihood of a successful inertisation.

关键词： GAG Inert gas Condensation Pressure loss Choked flow Gas velocity Borehole Heat transfer

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Hydrodynamic mechanisms of aggressive collapse events in leading edge cavitation

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Journal of Hydrodynamics 2020年第1期32卷 6-19页

作者： mohammad Hossein Arabnejad Ali Amini mohamed Farhat rickard EBensow Department of mechanics and maritime Sciences Chalmers University of TechnologyGothenburgSweden Laboratory for Hydraulic machines EPFLLausanneSwitzerland

Transient cavities generated from unsteady leading-edge cavitation may undergo aggressive collapses which are responsible for cavitation *** this paper,we studied the hydrodynamic mechanisms of these events in the leading edge cavitation fonned over a modified NACA0009 hydrofoil using experimental and numerical *** the experimental investigation,high-speed visualization(HSV)and paint test are employed to study the behavior of the cavitating flow at σ=1.25,α=5°,U∞=20 m/*** the numerical part,the same cavitating flow is simulated using an inviscid density-based compressible solver with a barotropic cavitation *** numerical results are first compared with the experimental HSV to show that the simulation is able to reproduce the main features of the cavitating ***,as the compressible solver is capable of capturing the shock wave upon the collapse of cavities,the location of collapse events with high erosion potential are *** location of these collapse events are compared with the paint test results with a qualitatively good *** is clearly observed,in both the experiments and the numerical simulation,that there exists four distinct regions along the hydrofoil with higher risks of erosion:(1)A very narrow strip at the leading edge,(2)an area of accumulated collapses at around 60 percent of the sheet cavity maximum length,(3)an area around the closure line of the sheet cavity with the highest erosion damage,and(4)a wide area close to the trailing edge with dispersed collapse events.A combined analysis of the experimental and numerical results reveals that the small-scale structures generated by secondary shedding are more aggressive than the large-scale cloud cavities(primary shedding).It is also observed that the high risk of cavitation erosion in regions 2 and 3 is mainly due to the collapses of the small cavity structures that are formed around the sheet cavity closure line or the rolling cloud cavity.

关键词： Hydrodynamic mechanisms aggressive collapse events high-speed visualization(HSV) paint test compressible simulation of cavitating flows

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Time-resolved, defect-hosted, trace element mobility in deformedWitwatersrand pyrite

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Geoscience Frontiers 2019年第1期10卷 55-63页

作者： Denis Fougerouse Steven m.Reddy Christopher L.Kirkland David W.Saxey William D.rickard Robert m.Hough School of Earth and Planetary Sciences The Institute for Geoscience Research (TIGeR) Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University CSIRO minerals Resources

The Pb isotopic composition of rocks is widely used to constrain the sources and mobility of melts and hydrothermal fluids in the Earth's crust. In many cases, the Pb isotopic composition appears to represent mixing of multiple Pb reservoirs. However, the nature, scale and mechanisms responsible for isotopic mixing are not well known. Additionally, the trace element composition of sulphide minerals are routinely used in ore deposit research, mineral exploration and environmental studies, though little is known about element mobility in sulphides during metamorphism and deformation. To investigate the mechanisms of trace element mobility in a deformed Witwatersrand pyrite(FeS_2), we have combined electron backscatter diffraction(EBSD) and atom probe microscopy(APm). The results indicate that the pyrite microstructural features record widely different Pb isotopic compositions, covering the entire range of previously published sulphide Pb compositions from the Witwatersrand basin. We show that entangled dislocations record enhanced Pb, Sb, Ni, Tl and Cu composition likely due to entrapment and short-circuit diffusion in dislocation cores. These dislocations preserve the Pb isotopic composition of the pyrite at the time of growth(~3 Ga) and show that dislocation intersections, likely to be common in deforming minerals, limit trace element mobility. In contrast, Pb, As, Ni, Co, Sb and Bi decorate a highangle grain boundary which formed soon after crystallisation by sub-grain rotation *** isotopic composition within this boundary indicates the addition of externally-derived Pb and trace elements during greenschist metamorphism at ~2 Ga. Our results show that discrete Pb reservoirs are nanometric in scale, and illustrate that grain boundaries may remain open systems for trace element mobility over 1 billion years after their formation.

关键词： Atom probe microscopy Nanoscale Nanogeochronology microstructure Isotope geochemistry Common Pb

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Effects of Victim Innocence and BJW （Belief in a Just World） Upon Derogation of an Ingroup/Outgroup Victim

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Psychology Research 2012年第2期2卷 135-141页

作者： rickard A. Sebby Lindsey m. Johnston Southeast missouri State University Cape Girardeau USA

According to the BJW (belief in a just world) theory, a person is more likely to derogate a victim when that victim threatens their BJW. An innocent victim and a victim who is more similar (an ingroup member) are more threatening to a person"s BJW than a non-innocent outgroup victim with such a threat resulting in greater victim derogation. In the present study, group membership and victim innocence were manipulated. Group membership was based on status (college students vs. non-college students). College students (n = 162) were randomly assigned to either a BJW threating or BJW confirming condition. A 2 × 2 × 2 ANOVA (analysis of variance) found an interaction between the BJW manipulation and group membership; participants whose BJW was threatened derogated the non-student (outgroup) more than the control. Contrary to expected results, the college student (ingroup) victim was not as highly derogated as the outgroup member. We suggest that more subtle social categories (not just differences associated with traditional racial or ethnic prejudice) may influence the ways individuals defend or reestablish their BJW.

关键词：受害者世界公正大学生随机分配相互作用方差分析威胁

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