scholarly journals Shock compression response of forsterite above 250 GPa

2016 ◽  
Vol 2 (8) ◽  
pp. e1600157 ◽  
Author(s):  
Toshimori Sekine ◽  
Norimasa Ozaki ◽  
Kohei Miyanishi ◽  
Yuto Asaumi ◽  
Tomoaki Kimura ◽  
...  
Keyword(s):  
Shock Compression ◽  
Large Scale ◽  
Extreme Conditions ◽  
Laser Shock ◽  
Endothermic Reactions ◽  
Wave Technique ◽  
Complex Structural ◽  
Rocky Planets ◽  
Laser Shock Wave ◽  
Impact Events

Forsterite (Mg2SiO4) is one of the major planetary materials, and its behavior under extreme conditions is important to understand the interior structure of large planets, such as super-Earths, and large-scale planetary impact events. Previous shock compression measurements of forsterite indicate that it may melt below 200 GPa, but these measurements did not go beyond 200 GPa. We report the shock response of forsterite above ~250 GPa, obtained using the laser shock wave technique. We simultaneously measured the Hugoniot and temperature of shocked forsterite and interpreted the results to suggest the following: (i) incongruent crystallization of MgO at 271 to 285 GPa, (ii) phase transition of MgO at 285 to 344 GPa, and (iii) remelting above ~470 to 500 GPa. These exothermic and endothermic reactions are seen to occur under extreme conditions of pressure and temperature. They indicate complex structural and chemical changes in the system MgO-SiO2 at extreme pressures and temperatures and will affect the way we understand the interior processes of large rocky planets as well as material transformation by impacts in the formation of planetary systems.

Effect of Laser Shock Wave Cleaning Direction on Particle Removal Behavior at Trenchs

2019 ◽  
Vol 25 (5) ◽  
pp. 257-262 ◽  
Author(s):  
Jin-Su Kim ◽  
Ahmed A. Busnaina ◽  
Jin-Goo Park
Keyword(s):  
Shock Wave ◽  
Particle Removal ◽  
Laser Shock ◽  
Laser Shock Wave

Analysis and experiment on deformation of sheet metal by laser shock wave

2006 ◽  
Vol 1 (4) ◽  
pp. 448-451 ◽  
Author(s):  
Chao-jun Yang ◽  
Yong-kang Zhang ◽  
Jian-zhong Zhou ◽  
Ming-xiong Ni ◽  
Jian-jun Du ◽  
...  
Keyword(s):  
Shock Wave ◽  
Sheet Metal ◽  
Laser Shock ◽  
Laser Shock Wave

Application of the method of dimensional analysis in laser-shock-wave processing of titanium alloys with shape memory

2021 ◽  
pp. 66-72
Author(s):  
Keyword(s):  
Shock Wave ◽  
Finite Element ◽  
Plastic Zone ◽  
Shape Memory ◽  
Dimensional Analysis ◽  
Peak Pressure ◽  
Laser Shock ◽  
Zone Depth ◽  
Peak Pressures ◽  
Laser Shock Wave

The processes of laser-shock-wave processing of NiTi alloys with shape memory effect are investigated by the methods of dimensional analysis and finite element modeling. The dependences of the depth of the plastic zone on the peak pressure in the shock wave and the duration of the laser pulse are obtained at different peak pressures. Keywords: shape memory alloys, laser-shock-wave processing, dimensional analysis, residual stresses, plastic zone depth. [email protected]

scholarly journals Research on Formation Mechanism of Dynamic Response and Residual Stress of Sheet Metal Induced by Laser Shock Wave

2018 ◽  
Vol 167 ◽  
pp. 05007
Author(s):  
Aixin Feng ◽  
Yupeng Cao ◽  
Heng Wang ◽  
Zhengang Zhang
Keyword(s):  
Shock Wave ◽  
Residual Stress ◽  
Dynamic Response ◽  
Formation Mechanism ◽  
Experimental Studies ◽  
Material Surface ◽  
Propagation Mechanism ◽  
Laser Shock ◽  
Surface Residual Stress ◽  
Laser Shock Wave

In order to reveal the quantitative control of the residual stress on the surface of metal materials, the relevant theoretical and experimental studies were carried out to investigate the dynamic response of metal thin plates and the formation mechanism of residual stress induced by laser shock wave. In this paper, the latest research trends on the surface residual stress of laser shock processing technology were elaborated. The main progress of laser shock wave propagation mechanism and dynamic response, laser shock, and surface residual stress were discussed. It is pointed out that the multi-scale characterization of laser and material, surface residual stress and microstructure change is a new hotspot in laser shock strengthening technology.

Dynamic response of surface micro-features subjected to a laser shock wave planishing technique

2018 ◽  
Vol 742 ◽  
pp. 54-65 ◽  
Author(s):  
Fengze Dai ◽  
Jie Geng ◽  
Xudong Ren ◽  
Jinzhong Lu ◽  
Shu Huang
Keyword(s):  
Shock Wave ◽  
Dynamic Response ◽  
Laser Shock ◽  
Micro Features ◽  
Laser Shock Wave

Biogc: A novel framework for biological network classification via machine learning

2021 ◽  
Vol 25 (5) ◽  
pp. 1153-1168
Author(s):  
Bentian Li ◽  
Dechang Pi ◽  
Yunxia Lin ◽  
Izhar Ahmed Khan
Keyword(s):  
Large Scale ◽  
Biological Network ◽  
Structural Information ◽  
Kernel Method ◽  
Small Scale ◽  
Network Data ◽  
Graph Classification ◽  
Accuracy Rate ◽  
Proposed Model ◽  
Complex Structural

Biological network classification is an eminently challenging task in the domain of data mining since the networks contain complex structural information. Conventional biochemical experimental methods and the existing intelligent algorithms still suffer from some limitations such as immense experimental cost and inferior accuracy rate. To solve these problems, in this paper, we propose a novel framework for Biological graph classification named Biogc, which is specifically developed to predict the label of both small-scale and large-scale biological network data flexibly and efficiently. Our framework firstly presents a simplified graph kernel method to capture the structural information of each graph. Then, the obtained informative features are adopted to train different scale biological network data-oriented classifiers to construct the prediction model. Extensive experiments on five benchmark biological network datasets on graph classification task show that the proposed model Biogc outperforms the state-of-the-art methods with an accuracy rate of 98.90% on a larger dataset and 99.32% on a smaller dataset.

New Finite Element Modeling Strategy for Large-Scale Industrial Problems in Structural Acoustics

2000 ◽  
Author(s):  
Saikat Dey ◽  
Luise S. Couchman
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Large Scale ◽  
Structural Acoustics ◽  
Simple Scheme ◽  
Numerical Examples ◽  
High Wave ◽  
Wave Numbers ◽  
Complex Structural ◽  
Modeling Strategy

Abstract A simple scheme to model and mesh stiffened shell-like structures is presented. Combined with a high-order finite/infinite element based infrastructure, it enables the solution of complex structural acoustics problems at high wave numbers. Numerical examples are presented to show the applicability of the method at high wave-numbers.

What Are Extremophiles?

2020 ◽  
pp. 157-176
Author(s):  
Carlos Mariscal ◽  
T.D.P. Brunet
Keyword(s):  
Large Scale ◽  
Extreme Conditions ◽  
Metabolic Processes

This chapter studies the concept of an extremophile. In the 1970s, R. D. MacElroy coined the term “extremophile” to describe microorganisms that thrive under extreme conditions. This hybrid word transliterates to “love of extremes” and has been studied as a straightforward concept ever since. The chapter then delineates five different ways to think about extremophiles, concluding that the concept is especially prone to the vagueness and arbitrariness that plague other biological categories, since it unavoidably involves debatable assumptions about life's nature and limits. These five concepts are, briefly, human-centric, at the edge of life's habitation of morphospace, by appeal to statistical rarity, described by objective limits, and at the limits of impossibility for metabolic processes. Importantly, these concepts have coexisted, unacknowledged and conflated, for decades. Confusion threatens to follow from the wildly varied inclusion or exclusion of organisms as extremophiles depending on the concept used. Under some conceptions, entire kinds of extremophiles become meaningless. Ultimately, since people's understanding of how life works is shaped by what people take to be its extremes, clarifying extremophily is key for many large-scale projects in biology, biotechnology, and astrobiology.

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