Segregation of high pressure partial melts from peridotite using aggregates of diamond: A New experimental approach

1992 ◽  
Vol 19 (16) ◽  
pp. 1703-1706 ◽  
Author(s):  
Kevin T. M. Johnson ◽  
Ikuo Kushiro
Keyword(s):  
High Pressure ◽  
Experimental Approach ◽  
Partial Melts

scholarly journals Minimizing Polymorphic Risk Through Cooperative Computational and Experimental Exploration

2020 ◽  
Author(s):  
Christopher R. Taylor ◽  
Matthew T. Mulvee ◽  
Domonkos S. Perenyi ◽  
Michael R. Probert ◽  
Graeme Day ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Structure Prediction ◽  
Experimental Approach ◽  
Significant Risk ◽  
Free Energy Calculations ◽  
Crystal Structure Prediction ◽  
Crystal Forms ◽  
Wide Range ◽  
Solid Form

<div> <p>We combine state-of-the-art computational crystal structure prediction (CSP) techniques with a wide range of experimental crystallization methods to understand and explore crystal structure in pharmaceuticals and minimize the risk of unanticipated late-appearing polymorphs. Initially, we demonstrate the power of CSP to rationalize the difficulty in obtaining polymorphs of the well-known pharmaceutical isoniazid and show that CSP provides the structure of the recently discovered, but unsolved, Form III of this drug despite there being only a single known form for almost 70 years. More dramatically, our blind CSP study predicts a significant risk of polymorphism for the related iproniazid. Employing a wide variety of experimental techniques, including high-pressure experiments, we experimentally obtained the first three known non-solvated crystal forms of iproniazid, all of which were successfully predicted in the CSP procedure. We demonstrate the power of CSP methods and free energy calculations to rationalize the observed elusiveness of the third form of iproniazid, the success of high-pressure experiments in obtaining it, and the ability of our synergistic computational-experimental approach to “de-risk” solid form landscapes.</p> </div>

Liquid sheet disintegration at high pressure: An experimental approach

2009 ◽  
Vol 337 (6-7) ◽  
pp. 481-491 ◽  
Author(s):  
V.G. Fernandez ◽  
P. Berthoumie ◽  
G. Lavergne
Keyword(s):  
High Pressure ◽  
Experimental Approach ◽  
Liquid Sheet

Partial Melts of Intermediate–Felsic Sources in a Wedged Thickened Crust: Insights from Granites in the Sulu Orogen

2020 ◽  
Vol 61 (5) ◽  
Author(s):  
Hongjie Wu ◽  
Yongsheng He ◽  
Shuguang Li ◽  
Chuanwei Zhu ◽  
Zhenhui Hou
Keyword(s):  
High Pressure ◽  
Large Scale ◽  
North China Block ◽  
Northern Margin ◽  
The North ◽  
Tanlu Fault ◽  
Wedge Structure ◽  
Partial Melts ◽  
Zircon Thermometry ◽  
Orogenic Belts

Abstract High-pressure (&gt;15 kbar) melts of intermediate–felsic materials have been well studied by experiments, whereas their existence in nature, especially in orogenic belts, is rarely examined. With the aim of identifying and characterizing high-pressure partial melts of intermediate–felsic continental crusts, this study presents comprehensive geochemical and geochronological data for 47 Jurassic granites (166∼157 Ma) from the Sulu orogen. These Sulu Jurassic granites (SJG) consist of quartz, K-feldspar and plagioclase with minor mineral assemblages of biotite ± muscovite ± garnet ± epidote ± allanite. Their low mafic mineral abundance, high SiO2 and Al2O3, and low FeOt + MgO contents show leucogranite-like affinities. They have low Mg#, low Rb/Sr, and mildly peraluminous features, collectively suggesting an intermediate–felsic orthogneissic source. Whole-rock Zr saturation thermometry and Ti-in-zircon thermometry together suggest initial magma temperatures between 695 ± 32 °C and 751 ± 27 °C (1 standard deviation), indicating derivation from water-present melting. The SJG notably feature high Sr contents (average 792 ppm), high Sr/CaO ratios (average 476) as well as inter-correlated low REE concentrations (average ΣREE 87 ppm), low Th concentrations (average 5·1 ppm) and positive Eu anomalies (Eu/Eu* up to 2·94). These characteristics are best explained by partial melting of intermediate–felsic sources under high pressure (&gt;15 kbar), leaving residuum where feldspar is sparse or absent and allanite is present. Inherited zircon age spectra and Sr–Nd–Pb isotopic compositions suggest that their source components could be mainly the Triassic orthogneisses whose protoliths are from the northern margin of the South China Block, probably in a wedge structure where the exhumed felsic slabs were wedged into the crust of the North China Block in the middle–late Jurassic and formed a stacked thickened crust. The wedge structure was most probably driven by synchronous large-scale strike-slip of the Tanlu fault, as a far-field effect of the oblique subduction of the paleo-Pacific plate. The characteristic chemical features observed in this study may be applied to identifying partial melts with similar petrogenesis elsewhere.

Analytical and Experimental Approach of Residual Stress on Deep-Rolled Crankshafts and Auto-Fretted Diesel Injection Rails. Effect on Fatigue Resistances in Service

2011 ◽  
Vol 681 ◽  
pp. 261-266 ◽  
Author(s):  
H. Michaud ◽  
Jean Michel Sprauel
Keyword(s):  
Residual Stress ◽  
High Pressure ◽  
Residual Stresses ◽  
Analytical Model ◽  
Fatigue Damage ◽  
Fatigue Resistance ◽  
Experimental Approach ◽  
Industrial Process ◽  
Diesel Injection ◽  
Fatigue Criterion

The fatigue resistance of car components such as crankshafts or diesel injection rails is mainly related to fatigue at geometrical singularities. Its understanding requires the simulations of the different steps of the industrial process resulting in residual stresses generation and their evolutions in service. First concerning crankshaft fatigue damage, a complete analytical model of residual stresses generation and shakedown in fatigue is presented. Then a fatigue criterion is established and validated for this application. Finally, for the high pressure diesel injection rail, this approach can be generalized to the holes intersection singularities.

scholarly journals A short, sharp pulse of potassium-rich volcanism during continental collision and subduction

Geology ◽  
2019 ◽  
Vol 47 (11) ◽  
pp. 1079-1082 ◽  
Author(s):  
M.R. Palmer ◽  
E.Y. Ersoy ◽  
C. Akal ◽  
İ. Uysal ◽  
Ş.C. Genç ◽  
...  
Keyword(s):  
High Pressure ◽  
Isotope Composition ◽  
Volcanic Rocks ◽  
Continental Collision ◽  
Western Anatolia ◽  
Slab Rollback ◽  
Tectonic Zones ◽  
Geochemical Indices ◽  
Partial Melts ◽  
Potassic Volcanism

Abstract Potassic volcanic rocks are characteristic of collisional tectonic zones, with recycling of continental crust playing an important role in their generation. Potassium-rich partial melts and/or fluids derived from subducted continental material initiate and/or mix with mantle-derived melts and then erupt at the surface with varying degrees of interaction with the overlying lithosphere. The details of how continental material incorporates into mantle melts are, however, uncertain. In particular, the depths from which the potassium-rich fluids and/or melts are released from the continental material and then react with the mantle-derived melts remain a subject of debate. We have measured the boron isotope composition of volcanic rocks from Western Anatolia (Turkey) that erupted between 52 and 0.1 Ma, and span the lifetime of collisional events from initial arc-type eruptions to post-collisional volcanism. These data and other geochemical indices show that ultrapotassic volcanism was mainly confined to a narrow window between ca. 20 and 15 Ma, consistent with recycling of high-pressure phengite, with the timing of the potassic volcanism coincident with slab rollback and breakoff.

scholarly journals Status of the R2D2 project: A future neutrinoless double beta decay experiment

2021 ◽  
Vol 2105 (1) ◽  
pp. 012016
Author(s):  
Ioannis Katsioulas
Keyword(s):  
High Pressure ◽  
Beta Decay ◽  
Energy Resolution ◽  
Experimental Approach ◽  
Neutrinoless Double Beta Decay ◽  
Large Mass ◽  
Double Beta Decay ◽  
Majorana Particle ◽  
Excellent Energy Resolution ◽  
Double Beta Decay Experiment

Abstract The nature of the neutrino is a central questions in physics. The search for neutrinoless double beta decay is the most sensitive experimental approach to demonstrate that the neutrino is a Majorana particle. Observation of such a rare process demands a detector with an excellent energy resolution, extremely low background, and a large mass of a double beta decaying isotope. R2D2 aims to develop a novel spherical high-pressure TPC that meets all the above requirements. As a first step, the energy resolution of the R2D2 prototype was measured. A 1.1% (FWHM) energy resolution was achieved for 5.3 MeV α-particles in Ar:CH4 at pressure up to 1.1 bar. This is a major milestone for R2D2 and paves the way for further studies with Xe gas and the possible use of this technology for neutrinoless double beta decay searches.

scholarly journals Thermobarometry of Diamond Inclusions: Evidence Mantle Evolution beneath Siberian Craton and Archean Cratons Worldwide.

2021 ◽  
Author(s):  
Igor Ashchepkov ◽  
Alla Logvinova ◽  
Zdislav Spetsius ◽  
Hilary Downes
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Middle Part ◽  
East European ◽  
Mantle Evolution ◽  
Mineral Inclusions ◽  
Amazonian Craton ◽  
Partial Melts ◽  
Continental Growth ◽  
Diamond Inclusions

Thermobarometric calculations for mineral inclusions in diamonds provide a systematic comparison of PTXFO2 conditions for different cratons worldwide, using a database of 4440 mineral EPMA analyses. Beneath all cratons, the cold branch of the mantle geotherm (35-32 mWm&minus;2) relates to the sub-Ca garnets and rarely omphacitic diamond inclusions, referring to major continental growth events in Archean. High-temperature plume-related geotherms are common in Proterozoic kimberlites such as Premier, Mesozoic &ndash; Roberts Victor etc. and are common in Slave and Siberian cratons. In mobile belts: Limpopo, Magondi, Ural Ural, Khapchan belts and in the marginal parts of cratons like Kimberly Australia pyroxenitic and eclogitic pyroxenes and garnets prevail. The pyropes in the mobile belts are more Fe- and Ca-rich, in central parts of cratons, the peridotitic associations with sub- Ca pyropes prevail. The accretionary complexes like Khapchan and Magondi belts a thick eclogite-pyroxenite lens is highly diamondiferous. Comparison by minerals shows that the PT estimates for clinopyroxenes and orthopyroxene from peridotites and eclogites are representing mainly the middle part of the sub-lithospheric mantle while garnets gives more high-pressure estimates. refer to eclogites and reflect the processes of the differentiation during migration of partial melts. This produces the trends of joint decreasing Mg&rsquo; and pressures. The PT for the chromites reflect conditions just above the lithosphere-asthenosphere boundary and mainly were formed due to interaction with the hydrous plume protokimberlite melts. Archean diamond inclusions from Wawa province Canada are represented by Ca-enrich pyropes giving low-temperature conditions. Inclusions from younger kimberlites in Superior and Slave (and Siberian and East European ) cratons show complex high-temperature geotherms due to plumes influence. Peridotite garnets beneath the Amazonian craton indicate complex layering in the lithosphere base and a pyroxene layer in the middle part of SCLM. Diamond inclusions from the Kimberley craton of Australia show the greatest variations in the temperatures and composition.

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