scholarly journals Water in omphacite fingerprints the thermal history of eclogites

Geology ◽  
2021 ◽  
Author(s):  
Peilin Jiang ◽  
Hanyong Liu ◽  
Henrik Skogby ◽  
Ren-Xu Chen ◽  
Xiaozhi Yang

Omphacite is a diagnostic mineral of high- and ultrahigh-pressure rocks, and its association with garnet is characteristic of eclogites from subduction-related massifs and volcano-entrained xenoliths. Omphacite can accommodate significant amounts of water as structurally bound hydroxyl (OH) groups, and is able to convey water into Earth’s interior. We show, for the first time, experimental evidence that the infrared absorption patterns of water in omphacite are temperature sensitive. This provides a new framework for discriminating water in natural omphacite equilibrated at different temperatures. We also demonstrate that in low-temperature omphacite, the integral absorbance ratio between the infrared OH absorption bands at 3620 cm–1 and 3450 cm–1 is linearly related to temperature. Water in omphacite of massif eclogites records the temperature of OH equilibrium, allowing reconstruction of the fluid-involved thermal history and tectonics of rock evolution.

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1111
Author(s):  
Francis J. Sousa ◽  
Kenneth A. Farley

This paper presents a framework for evaluating variation in (U-Th)/He datasets. The framework is objective, repeatable, and based on compatibility of thermal histories derived from individual (U-Th)/He dates. The structure of this new method includes three fundamental steps. First, the allowable thermal history of each individual grain is quantitatively constrained with a model. Second, the thermal histories of all grains from a sample are visualized on the same axes. Third, the compatibility of the allowable thermal histories of each individual grain is evaluated. This allows a user to assess whether variation among single grain dates can plausibly be explained (referred to here as legitimate) or not (illegitimate). Additionally, this methodology allows for accurate representation of the impact that illegitimate variation has on the thermal history constraints of a sample. We demonstrate the application of this new framework using a variety of examples from the literature, as well as with synthetic data. Modeling presented here is executed using the modeling software QTQt (version 5.6.0) and the He diffusion kinetics based on the radiation damage accumulation and annealing model, but the framework is designed to be easily adaptable to any modeling software and diffusion parameters.


Author(s):  
A. Rabhiou ◽  
J. Feist ◽  
A. Kempf ◽  
S. Skinner ◽  
A. Heyes

The thermal history of hot surfaces is of great practical importance, but very hard to measure. Thermal indicating paints offer one possible and practical way, but they have many disadvantages. A novel concept for the utilisation of phosphorescent coatings as thermal history sensors has been proposed by Feist et al. [1] in 2007. These phosphor coatings undergo irreversible changes when exposed to high temperatures that affect their light emission properties. A subsequent off-line analysis of the emission at room temperature can reveal the temperature history of the coating. In this paper, an investigation of the amorphous-to-crystalline change of Y2SiO5: Tb is reported and used to provide a proof of concept for a phosphorescent thermal history sensor. The phosphor powder was calcined at different temperatures, and characterised using photoluminescence spectroscopy. A calibration curve was generated from the measurements and is presented and discussed.


2018 ◽  
Vol 869 (1) ◽  
pp. 41 ◽  
Author(s):  
Jiao He ◽  
SM Emtiaz ◽  
Adwin Boogert ◽  
Gianfranco Vidali

2013 ◽  
Vol 40 (2) ◽  
pp. 244-256 ◽  
Author(s):  
Holger Funk

In the history of botany, Adam Zalužanský (d. 1613), a Bohemian physician, apothecary, botanist and professor at the University of Prague, is a little-known personality. Linnaeus's first biographers, for example, only knew Zalužanský from hearsay and suspected he was a native of Poland. This ignorance still pervades botanical history. Zalužanský is mentioned only peripherally or not at all. As late as the nineteenth century, a researcher would be unaware that Zalužanský’s main work Methodi herbariae libri tres actually existed in two editions from two different publishers (1592, Prague; 1604, Frankfurt). This paper introduces the life and work of Zalužanský. Special attention is paid to the chapter “De sexu plantarum” of Zalužanský’s Methodus, in which, more than one hundred years before the well-known De sexu plantarum epistola of R. J. Camerarius, the sexuality of plants is suggested. Additionally, for the first time, an English translation of Zalužanský’s chapter on plant sexuality is provided.


2008 ◽  
Vol 1 (2) ◽  
pp. 139-155 ◽  
Author(s):  
YAEL DARR

This article describes a crucial and fundamental stage in the transformation of Hebrew children's literature, during the late 1930s and 1940s, from a single channel of expression to a multi-layered polyphony of models and voices. It claims that for the first time in the history of Hebrew children's literature there took place a doctrinal confrontation between two groups of taste-makers. The article outlines the pedagogical and ideological designs of traditionalist Zionist educators, and suggests how these were challenged by a group of prominent writers of adult poetry, members of the Modernist movement. These writers, it is argued, advocated autonomous literary creation, and insisted on a high level of literary quality. Their intervention not only dramatically changed the repertoire of Hebrew children's literature, but also the rules of literary discourse. The article suggests that, through the Modernists’ polemical efforts, Hebrew children's literature was able to free itself from its position as an apparatus controlled by the political-educational system and to become a dynamic and multi-layered field.


2020 ◽  
Vol 72 (2) ◽  
Author(s):  
Tomasz Dzieńkowski ◽  
Marcin Wołoszyn ◽  
Iwona Florkiewicz ◽  
Radosław Dobrowolski ◽  
Jan Rodzik ◽  
...  

The article discusses the results of the latest interdisciplinary research of Czermno stronghold and its immediate surroundings. The site is mentioned in chroniclers’ entries referring to the stronghold Cherven’ (Tale of Bygone Years, first mention under the year 981) and the so-called Cherven’ Towns. Given the scarcity of written records regarding the history of today’s Eastern Poland, Ukraine, and Belarus in the 10th and 11th centuries, recent archaeological research, supported by geoenvironmental analyses and absolute dating, brought a significant qualitative change. In 2014 and 2015, the remains of the oldest rampart of the stronghold were uncovered for the first time. A series of radiocarbon datings allows us to refer the erection of the stronghold to the second half/late 10th century. The results of several years’ interdisciplinary research (2012-2020) introduce qualitatively new data to the issue of the Cherven’ Towns, which both change current considerations and confirm the extraordinary research potential in the archeology of the discussed region.


Author(s):  
Michael D. Gordin

Dmitrii Mendeleev (1834–1907) is a name we recognize, but perhaps only as the creator of the periodic table of elements. Generally, little else has been known about him. This book is an authoritative biography of Mendeleev that draws a multifaceted portrait of his life for the first time. As the book reveals, Mendeleev was not only a luminary in the history of science, he was also an astonishingly wide-ranging political and cultural figure. From his attack on Spiritualism to his failed voyage to the Arctic and his near-mythical hot-air balloon trip, this is the story of an extraordinary maverick. The ideals that shaped his work outside science also led Mendeleev to order the elements and, eventually, to engineer one of the most fascinating scientific developments of the nineteenth century. This book is a classic work that tells the story of one of the world's most important minds.


Author(s):  
Rachel Ablow

The nineteenth century introduced developments in science and medicine that made the eradication of pain conceivable for the first time. This new understanding of pain brought with it a complex set of moral and philosophical dilemmas. If pain serves no obvious purpose, how do we reconcile its existence with a well-ordered universe? Examining how writers of the day engaged with such questions, this book offers a compelling new literary and philosophical history of modern pain. The book provides close readings of novelists Charlotte Brontë and Thomas Hardy and political and natural philosophers John Stuart Mill, Harriet Martineau, and Charles Darwin, as well as a variety of medical, scientific, and popular writers of the Victorian age. The book explores how discussions of pain served as investigations into the status of persons and the nature and parameters of social life. No longer conceivable as divine trial or punishment, pain in the nineteenth century came to seem instead like a historical accident suggesting little or nothing about the individual who suffers. A landmark study of Victorian literature and the history of pain, the book shows how these writers came to see pain as a social as well as a personal problem. Rather than simply self-evident to the sufferer and unknowable to anyone else, pain was also understood to be produced between persons—and even, perhaps, by the fictions they read.


2020 ◽  
Vol 4 (1) ◽  
pp. 67-86
Author(s):  
Elisabeth Heyne

AbstractAlthough visual culture of the 21th century increasingly focuses on representation of death and dying, contemporary discourses still lack a language of death adequate to the event shown by pictures and visual images from an outside point of view. Following this observation, this article suggests a re-reading of 20th century author Elias Canetti. His lifelong notes have been edited and published posthumously for the first time in 2014. Thanks to this edition Canetti's short texts and aphorisms can be focused as a textual laboratory in which he tries to model a language of death on experimental practices of natural sciences. The miniature series of experiments address the problem of death, not representable in discourses of cultural studies, system theory or history of knowledge, and in doing so, Canetti creates liminal texts at the margins of western concepts of (human) life, science and established textual form.


2018 ◽  
Vol 33 (2) ◽  
Author(s):  
Mbuzeni Mathenjwa

The history of local government in South Africa dates back to a time during the formation of the Union of South Africa in 1910. With regard to the status of local government, the Union of South Africa Act placed local government under the jurisdiction of the provinces. The status of local government was not changed by the formation of the Republic of South Africa in 1961 because local government was placed under the further jurisdiction of the provinces. Local government was enshrined in the Constitution of the Republic of South Africa arguably for the first time in 1993. Under the interim Constitution local government was rendered autonomous and empowered to regulate its affairs. Local government was further enshrined in the final Constitution of 1996, which commenced on 4 February 1997. The Constitution refers to local government together with the national and provincial governments as spheres of government which are distinctive, interdependent and interrelated. This article discusses the autonomy of local government under the 1996 Constitution. This it does by analysing case law on the evolution of the status of local government. The discussion on the powers and functions of local government explains the scheme by which government powers are allocated, where the 1996 Constitution distributes powers to the different spheres of government. Finally, a conclusion is drawn on the legal status of local government within the new constitutional dispensation.


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