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Journal articles on the topic 'Coesine'

Author: Grafiati

Published: 9 March 2023

Last updated: 10 March 2023

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1

Martínez, J. R., A. Vázquez-Durán, G. Martínez-Castañón, G. Ortega-Zarzosa, S. A. Palomares-Sánchez, and Facundo Ruiz. "Coesite Formation at Ambient Pressure and Low Temperatures." Advances in Materials Science and Engineering 2008 (2008): 1–6. http://dx.doi.org/10.1155/2008/406067.

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Partial crystallization of silica xerogel in the form of coesite has been obtained at low-pressure conditions and temperatures of∼565∘C, in samples containing chlorophyll aggregates dispersed in amorphous silica. Silica xerogel samples were prepared by the sol-gel method using an ethanol:H2O:TEOS molar ratio of 4:11.6:1 and loaded with extracts from frozen spinach leaves. The silica xerogel microstructure of the powders was studied as a function of annealing temperature. It was found that partial crystallization of the glass matrix in the form of coestite was obtained at lower pressure than those specified by the phase diagram. Chlorophyll aggregates were added to the starting solutions which, upon thermal treatments, form small colloidal particles in the glass matrix. The presence of coesite is corroborated by the Rietveld refinement method.

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2

Wirth, R. "Microstructure of quartz in partially inverted coesite from high-pressure metamorphic rocks." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 462–63. http://dx.doi.org/10.1017/s0424820100170049.

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Coesite, a high-pressure polymorph of SiO2, was firstly synthesized by Coes. Naturally occurring coesite has been found in shock metamorphosed rocks, xenoliths in kimberlites, eclogites and metasediments. Coesite in metasediments indicates subduction of slabs of continental crust to depths of at least 90 km. Coesite can only survive obduction (decrease of P,T) as an inclusion in a high strength mineral like garnet (pyrope). Depending on the elastic behavior of the coesite-includmg garnets, coesite is always partially inverted into quartz. Stress associated with the volume increase due to the coesite inversion causes a radiating crack pattern around the including mineral. Complete failure of the pressure vessel results in a replacement of coesite by pseudomorphs of quartz after coesite. The present study intends to find characteristic microstructural features as reliable indicators for quartz pseudomorphs having been pseudomorphs after coesite. Four different types of quartz can be distinguished with respect to the fabric, due to the coesite inversion:

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3

Marinho, Janice Helena Chaves. "Coesão textual: o articulador "onde"." Revista do Centro de Estudos Portugueses 18, no. 23 (December 31, 1998): 209. http://dx.doi.org/10.17851/2359-0076.18.23.209-222.

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<p>Este trabalho pretende apresentar uma análise preliminar do<br />uso de um mecanismo coesivo – o articulador onde – em<br />textos orais e escritos, produzidos por alunos e professores<br />universitários. Pretendo mostrar, através de exemplos extraídos<br />de vários textos, diferentes usos desse mecanismo bem como<br />discutir sua atuação tanto no âmbito da sentença quanto no<br />âmbito do discurso.</p><p>This paper presents a preliminary analysis of the use of the<br />item onde (where) in oral and written texts produced by<br />university students and professors. We intend to show, through<br />several examples found in many texts, different uses of this<br />coesive mechanism and also to discuss a possible enlargement<br />of its field of action.</p>

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4

Mikhailenko, D. S., A. V. Korsakov, O. V. Rezvukhina, A. V. Golovin, and N. V. Sobolev. "Coesite inclusion in diamondferous kyanite-bearing eclogite from kimberlite pipe Udachnaya (Siberian Craton)." Доклады Академии наук 487, no. 4 (August 27, 2019): 428–31. http://dx.doi.org/10.31857/s0869-56524874428-431.

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A find of coesite in a kyanite graphite-diamond-bearing eclogite xenolith from the Udachnaya-Vostochnaya kimberlite pipe is described in this paper. The coesite relics were found in intensely fractured garnet indicating some influence of the kimberlite melt, which is supported by the typical secondary mineral assemblage around this inclusion. These data indicate that shallower diamond-free coesite rocks (2,7 GPa) underwent metamorphism distinct from diamond-bearing coesite eclogites (~4 GPa). The metasomatic alteration of rock interacting with C-O-H fluid during diamond crystallization may be another possible reason for the missing coesite in diamond-bearing xenoliths.

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5

Monaci, Maria Grazia, Rosanna Trentin, and Valentina Fanelli. "La competenza emotiva come antecedente della coesione e della soddisfazione nei gruppi di auto mutuo aiuto." GRUPPI, no. 2 (April 2011): 85–104. http://dx.doi.org/10.3280/gru2010-002007.

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Il presente studio esplora le relazioni fra competenza emotiva, coesione di gruppo e soddisfazione percepita della partecipazione a gruppi di auto mutuo aiuto, nell'ipotesi che la competenza emotiva aumenti la coesione di gruppo, e che la coesione agisca come un mediatore della relazione fra competenza emotiva e soddisfazione. Un questionario č stato somministrato a 89 (62F) partecipanti di gruppi di auto mutuo aiuto con diverse finalitŕ (problemi familiari, elaborazione del lutto, dipendenze, salute mentale, disabilitŕ). Il questionario comprende la versione italiana della Emotional Intelligence Assessment; due strumenti tratti dalla batteria di test "Ass3D" di Zammuner e Kafetsios, che rilevano la regolazione delle emozioni e la capacitŕ nel riconoscimento facciale; il GEQ, che misura la coesione sociale e sul compito; infine, un feeling thermometer che misura il grado di soddisfazione. Un'analisi strutturale mostra che l'intelligenza emotiva promuove la coesione e che, a sua volta, la coesione sociale incrementa la soddisfazione della partecipazione al gruppo, confermandone il ruolo di mediazione. Le implicazioni per incoraggiare la partecipazione in gruppi di auto mutuo aiuto e i possibili sviluppi di ricerca sono discusse.

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6

Wang, De Jun, Run Ru Liu, Leng Jing, and Xin Yu Bai. "The Synthesis from α-SiO₂ and Graphite System to Coesite under High Temperature High Pressure." Advanced Materials Research 1051 (October 2014): 299–302. http://dx.doi.org/10.4028/www.scientific.net/amr.1051.299.

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Taking α-quartz of different mass ratio mixed with graphite powder mixture as the initial materials, using the method of combining high-energy mechanical milling with high pressure and high temperature , this work inspected the influences of carbon content on the synthesis conditions of coesite. The experimental products were measured by XRD, TEM, and Raman. The results showed that the existence of carbon can obviously inhibit the formation of coesite, and the higher carbon content of initial materials the higher pressure on forming coesite is needed.

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7

Wang, De Jun, Run Ru Liu, and Leng Jing. "The Formation of Coesite under Minimum Static Pressure." Applied Mechanics and Materials 675-677 (October 2014): 38–41. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.38.

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Using the α-SiO2 and conducted by high-energy mechanical milling as the initial material, we investigated the synthesis of coesite under high temperature and high pressure in the condition of adding a certain amount of hard Fe fillings. The synthetic samples are measured by XRD and Raman, and the results show that a small amount of small-sized coesite can be obtained under 2.5 GPa. Based on these results, it is considered that the forming depth of natural coesite under the earth is likely to be obviously shallower than that of plate exhumation in the traditional subduction-exhumation hypothesis.

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8

Barbosa, Raísa Cristina Madeira, Nielsen Barros Souza, Adriana de Fátima Vasconcelos Pereira, Vandílson Pinheiro Rodrigues, and Ivone Lima Santana. "ANÁLISE DO PADRÃO DE FRATURAS EM PINOS ANATOMIZADOS CIMENTADOS COM DIFERENTES AGENTES CIMENTANTES." Iniciação Científica Cesumar 19, no. 2 (December 5, 2017): 145. http://dx.doi.org/10.17765/1518-1243.2017v19n2p145-151.

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O objetivo do presente estudo foi investigar, in vitro, o padrão de fratura em dentes com pino de fibra de vidro (PFV) anatomizado e fixado com diferentes agentes cimentantes. Foram utilizados 30 dentes bovinos mandibulares unirradiculares. As raízes foram tratadas endodonticamente e divididas aleatoriamente em dois grupos, de acordo com o agente cimentante utilizado, em G1: cimento resinoso autoadesivo (RelyX U200-3M ESPE); G2: cimento resinoso convencional (Allcem-FGM). Após a anatomização e cimentação dos pinos, os espécimes foram armazenados em estufa, a 37ºC, por sete dias. Em seguida, foi realizada a secção das raízes, sob irrigação constante, obtendo-se de cada raiz seis fatias de 1 mm de espessura, totalizando 180 corpos de prova. O teste de resistência à extrusão (push-out) foi realizado em todos os espécimes, e posteriormente, os corpos de prova foram observados em microscópio ótico de luz, para avaliar os tipos de fratura. O tipo de fratura mais frequente em ambos os grupos foi a coesina em dentina (G1 = 32,2%; G2 = 30%). Observou-se frequência estatisticamente maior de falhas adesivas entre dentina e cimento no grupo G2 (P = 0,007). Além disso, detectou-se frequência estatisticamente mais elevada (P = 0,027) de fratura coesiva em dentina no terço cervical (38,3%) quando comparado ao terço apical (20,0%). Os achados sugerem que o cimento autoadesivo (RelyX U200-3M ESPE) apresentou resultados mais favoráveis quando da análise do padrão de fraturas.

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9

Ren, Dongsheng. "Study on the Phase Transition from Quartz to Coesite under High Temperature and High Pressure." Minerals 12, no. 8 (July 29, 2022): 963. http://dx.doi.org/10.3390/min12080963.

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Quartz is an important component of the Earth. In this study, experiments were conducted at temperatures between 600 to 700 °C, confining pressures between 1.5 and 1.8 GPa, and differential stress conditions. It was found that coesite production is closely related to differential stress, reaction time, and reaction temperature, with coesite formation being a multifactorial coupling process.

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10

Trukhin, A. N., K. Smits, J. Jansons, G. Chikvaidze, T. I. Dyuzheva, and L. M. Lityagina. "Luminescence of coesite." Physica Scripta 90, no. 9 (August 13, 2015): 094009. http://dx.doi.org/10.1088/0031-8949/90/9/094009.

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11

Ganugi, Giulia, and Riccardo Prandini. "Problematizzare la coesione sociale urbana attraverso l'engagement collettivo e la responsabilità condivisa. I casi di due Social Street italiane." SOCIOLOGIA URBANA E RURALE, no. 127 (March 2022): 137–53. http://dx.doi.org/10.3280/sur2022-127011.

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Questo contributo riflette sulla coesione sociale, indagando i processi che ne favoriscono lo sviluppo a scala locale tramite le dimensioni di engagement collettivo e responsabilità condivisa. Il quadro concettuale viene applicato a due Social Street con una metodologia qualitativa. I risultati evidenziano la contingenza di engagement collettivo e responsabilità condivisa, la genesi di episodi di coesione sociale e l'importanza di interfacce riflessive tra gli attori comunitari e istituzionali.

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12

Schönig, Jan, Hilmar von Eynatten, Guido Meinhold, and N. Keno Lünsdorf. "Diamond and coesite inclusions in detrital garnet of the Saxonian Erzgebirge, Germany." Geology 47, no. 8 (May 22, 2019): 715–18. http://dx.doi.org/10.1130/g46253.1.

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Abstract Local occurrences of coesite- and diamond-bearing rocks in the central Erzgebirge (northwestern Bohemian Massif, Germany) reveal ultrahigh-pressure (UHP) metamorphic conditions during the Variscan orogeny. Although UHP metamorphism supposedly affected a wider area, implying that rocks that equilibrated under UHP conditions occur dispersed in large volumes of high-pressure country-rock gneisses, mineralogical evidence is scarce. Here we have applied the new concept of capturing the distribution and characteristics of UHP rocks by analyzing inclusions in detrital garnet. Out of 700 inclusion-bearing garnets from seven modern sand samples from creeks draining the UHP area around the Saidenbach reservoir, we detected 26 garnets containing 46 mainly monomineralic coesite inclusions and 22 garnets containing 41 diamond inclusions. Combining these results with geochemical classification of the host garnets, we show (1) that coesite-bearing rocks are common and comprise eclogites as well as felsic gneisses, (2) that small inclusion size is a necessary precondition for the preservation of monomineralic coesite, and (3) for the first time, that diamond-bearing crustal rocks can be detected by analyzing the detrital record. Our results highlight the potential of this novel application of sedimentary provenance tools to UHP research, and the necessity of looking at the micrometer scale to find evidence in the form of preserved UHP minerals.

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13

Bergholz, W., and J. L. Hutchison. "Early stages of oxygen precipitation in si: morphology and structure." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 478–79. http://dx.doi.org/10.1017/s0424820100104455.

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Intrinsic gettering in Si - VLSI technology depends on a controlled initial stage of oxygen precipitation and is characterized by a complicated interaction of growth-induced microdefects, self interstitial (SiI) generation and strain caused by SiO2 precipitate growth and secondary defects, table 1. We address the controversial issues of the identity of ribbon-like defects (RLDs) and of the nature of oxygen precipitate nuclei.RLDs were initially identified by HRTEM as coesite, a high pressure phase of SiO2. Recently, both Bourret and Reiche et al have interpreted the RLDs as hexagonal Si, or agglomerates of Si. We wish to make the point that the evidence against coesite is, as yet, not conclusive, and present circumstantial evidence in favour of coesite: (1) The loss of interstitial oxygen correlates with the density of RLDs (Fig. 1) at 450 - 485°C.

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14

Thomas, Rainer, Paul Davidson, Adolf Rericha, and Ulrich Recknagel. "Discovery of Stishovite in the Prismatine-Bearing Granulite from Waldheim, Germany: A Possible Role of Supercritical Fluids of Ultrahigh-Pressure Origin." Geosciences 12, no. 5 (May 4, 2022): 196. http://dx.doi.org/10.3390/geosciences12050196.

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For the first time in the sixty years since the synthesis of stishovite, we report unambiguous evidence of stishovite formed in the deep Earth. A minimum pressure of about 7.5 GPa at 1000 °C is necessary for the formation of stishovite, corresponding to a depth of about 230 km. In this manuscript we report the identification of stishovite along with coesite as inclusions in mineral grains from the Waldheim granulite. This implies that the stishovite was transported upwards, probably very rapidly to a depth of about 130 km, corresponding to the highest pressure indicated by newly identified coesite in the prismatine of the Waldheim granulite, and continuing up to the depth of emplacement of the Waldheim prismatine granulite. The analysis of the Raman spectra obtained from a metastable trapped stishovite micro-crystal show that all the diagnostic Raman bands are present. However, given the metastability of the stishovite at room temperatures and pressures, this mineral breaks down step-by-step into stable polymorphs, first coesite and then quartz and cristobalite, during the Raman stimulation. The rare coesite crystals in prismatine have also resulted from the irreversible transformation from stishovite. Although the Waldheim occurrence may be unique, we suggest that Raman analysis of co-trapped crystals in similar deep-seated rocks, an area of limited previous research, may prove an important innovation in the study of mantle processes.

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15

Asano, Kouhei, Katsuyoshi Michibayashi, and Tomohiro Takebayashi. "Rheological Contrast between Quartz and Coesite Generates Strain Localization in Deeply Subducted Continental Crust." Minerals 11, no. 8 (August 4, 2021): 842. http://dx.doi.org/10.3390/min11080842.

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Deformation microstructures of peak metamorphic conditions in ultrahigh-pressure (UHP) metamorphic rocks constrain the rheological behavior of deeply subducted crustal material within a subduction channel. However, studies of such rocks are limited by the overprinting effects of retrograde metamorphism during exhumation. Here, we present the deformation microstructures and crystallographic-preferred orientation data of minerals in UHP rocks from the Dabie–Shan to study the rheological behavior of deeply subducted continental material under UHP conditions. The studied samples preserve deformation microstructures that formed under UHP conditions and can be distinguished into two types: high-strain mafic–ultramafic samples (eclogite and garnet-clinopyroxenite) and low-strain felsic samples (jadeite quartzite). This distinction suggests that felsic rocks are less strained than mafic–ultramafic rocks under UHP conditions. We argue that the phase transition from quartz to coesite in the felsic rocks may explain the microstructural differences between the studied mafic–ultramafic and felsic rock samples. The presence of coesite, which has a higher strength than quartz, may result in an increase in the bulk strength of felsic rocks, leading to strain localization in nearby mafic–ultramafic rocks. The formation of shear zones associated with strain localization under HP/UHP conditions can induce the detachment of subducted crustal material from subducting lithosphere, which is a prerequisite for the exhumation of UHP rocks. These findings suggest that coesite has an important influence on the rheological behavior of crustal material that is subducted to coesite-stable depths.

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16

Nato, Alessandro, and Marta Simoncini. "Innovazioni e criticità nel rilancio del processo di integrazione attraverso l'economia e la moneta." DIRITTO COSTITUZIONALE, no. 2 (July 2022): 11–30. http://dx.doi.org/10.3280/dc2022-002002.

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Nel corso della pandemia le istituzioni europee si sono impegnate a promuovere la coesione economico-sociale e scongiurare la crisi delle economie europee attraverso l'adozione di misure atte a favorire la ripresa economica. Questo contributo si propone di analizzare tre diversi aspetti dell'intervento dell'UE nell'economia. In primo luogo, viene esaminato il modello di governance previsto nel contesto del cd. Next Generation EU package. Vengono, quindi, analizzati i meccanismi di condizionalità che subordinano l'accesso ai finanziamenti al rispetto di diversi obiettivi di policy europei. Infine, si esami-na il ruolo della BCE nella promozione della coesione.

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17

Wehinger, Björn, Alexeï Bosak, Aleksandr Chumakov, Alessandro Mirone, Björn Winkler, Leonid Dubrovinsky, Natalia Dubrovinskaia, Vadim Brazhkin, Tatiana Dyuzheva, and Michael Krisch. "Lattice dynamics of coesite." Journal of Physics: Condensed Matter 25, no. 27 (June 17, 2013): 275401. http://dx.doi.org/10.1088/0953-8984/25/27/275401.

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18

Angel, R. J., C. S. J. Shaw, and G. V. Gibbs. "Compression mechanisms of coesite." Physics and Chemistry of Minerals 30, no. 3 (April 1, 2003): 167–76. http://dx.doi.org/10.1007/s00269-003-0303-9.

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19

Pappalardo, Giusy. "Coesione territoriale e coesione interna nelle Aree Interne: questioni di governance d'area." TERRITORIO, no. 89 (November 2019): 112–22. http://dx.doi.org/10.3280/tr2019-089015.

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20

Wu, Ye, Shengxuan Huang, Haijun Huang, Xiang Wu, and Hanyu Liu. "Structural characteristics and elasticities of coesite and coesite-II at high pressure." New Journal of Physics 22, no. 9 (September 15, 2020): 093044. http://dx.doi.org/10.1088/1367-2630/abb0fd.

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21

Liu, Penglei, Hans-Joachim Massonne, Junfeng Zhang, Yao Wu, and Zhenmin Jin. "Intergranular coesite and coesite inclusions in dolomite from the Dabie Shan: Constraints on the preservation of coesite in UHP rocks." Terra Nova 29, no. 3 (March 26, 2017): 154–61. http://dx.doi.org/10.1111/ter.12258.

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22

Kovalenko, Mikhail, Denis Shalkovsky, Aleksandr Petrovtsev, Aleksandr Pavlenko, Svetlana Malyugina, and Dmitriy Yusupov. "Simulation of phase transitions and strength evolution in quartzite in shock experiments." EPJ Web of Conferences 250 (2021): 02030. http://dx.doi.org/10.1051/epjconf/202125002030.

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Quartzite is a basic rock constituent. It has a complicated phase diagram where besides a low-pressure phase (α-quartz), two high-pressure solid ones are present – coesite and stishovite. Also present are the hightemperature cristobalite and tridymite phases with very small stability regions. In shock experiments, the transition to coesite almost never realizes and the transition from α-quartz to stishovite proceeds in a strongly nonequilibrium regime characterized by metastability and a long transition time. Quartzite is polycrystalline quartz with small amounts of impurities. The paper describes experiments with samples of Pervouralsk quartzite with mass fractions of SiO2 above 96%.

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23

Liu, Wei, Xuebang Wu, Yunfeng Liang, Changsong Liu, Caetano R. Miranda, and Sandro Scandolo. "Multiple pathways in pressure-induced phase transition of coesite." Proceedings of the National Academy of Sciences 114, no. 49 (November 21, 2017): 12894–99. http://dx.doi.org/10.1073/pnas.1710651114.

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High-pressure single-crystal X-ray diffraction method with precise control of hydrostatic conditions, typically with helium or neon as the pressure-transmitting medium, has significantly changed our view on what happens with low-density silica phases under pressure. Coesite is a prototype material for pressure-induced amorphization. However, it was found to transform into a high-pressure octahedral (HPO) phase, or coesite-II and coesite-III. Given that the pressure is believed to be hydrostatic in two recent experiments, the different transformation pathways are striking. Based on molecular dynamic simulations with an ab initio parameterized potential, we reproduced all of the above experiments in three transformation pathways, including the one leading to an HPO phase. This octahedral phase has an oxygen hcp sublattice featuring 2 × 2 zigzag octahedral edge-sharing chains, however with some broken points (i.e., point defects). It transforms into α-PbO2 phase when it is relaxed under further compression. We show that the HPO phase forms through a continuous rearrangement of the oxygen sublattice toward hcp arrangement. The high-pressure amorphous phases can be described by an fcc and hcp sublattice mixture.

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Mikhailenko, D. S., D. I. Rezvukhin, A. V. Korsakov, and N. V. Sobolev. "Olivine in a coesite-bearing eclogite from the Udachnaya kimberlite pipe." Доклады Академии наук 489, no. 3 (November 29, 2019): 286–91. http://dx.doi.org/10.31857/s0869-56524893286-291.

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Olivine (high-Fe forsterite; Fo# 69-76) and associated minerals have been studied in a coesite-bearing diamon-diferous eclogite from the Udachnaya-East kimberlite pipe. Olivine was identified in the rock interstices together with K‑feldspar, sodalite, phlogopite and djerfisherite. The composition of individual olivine grains varies within the xenolith and is characterized by a consistent presence of P2O5, MnO, CaO и Al2O3. The coexistence of olivine and coesite is uncommon for mantle xenoliths. The occurrence of olivine and K, Na, Сl-bearing minerals in the studied sample is suggested to have been caused by the interaction of the eclogite with a protokimberlitic melt enriched in alkali components and chlorine.

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25

Miao, Yunfan, Youwei Pang, Yu Ye, Joseph R. Smyth, Junfeng Zhang, Dan Liu, Xiang Wang, and Xi Zhu. "Crystal Structures and High-Temperature Vibrational Spectra for Synthetic Boron and Aluminum Doped Hydrous Coesite." Crystals 9, no. 12 (December 5, 2019): 642. http://dx.doi.org/10.3390/cryst9120642.

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Coesite, a high-pressure SiO2 polymorph, has drawn extensive interest from the mineralogical community for a long time. In this study, we synthesized hydrous coesite samples with different B and Al concentrations at 5 and 7.5 GPa (1273 K). The B concentration could be more than 400 B/106Si with about 300 ppmw H2O, while the Al content can be as much as 1200 to 1300 Al/106Si with CH2O restrained to be less than 10 ppmw. Hence, B-substitution may prefer the mechanism of Si4+ = B3+ + H+, whereas Al-substitution could be dominated by 2Si4+ = 2Al3+ + OV. The doped B3+ and Al3+ cations may be concentrated in the Si1 and Si2 tetrahedra, respectively, and make noticeable changes in the Si–O4 and Si–O5 bond lengths. In-situ high-temperature Raman and Fourier Transformation Infrared (FTIR) spectra were collected at ambient pressure. The single crystals of coesite were observed to be stable up to 1500 K. The isobaric Grüneisen parameters (γiP) of the external modes (<350 cm−1) are systematically smaller in the Al-doped samples, as compared with those for the Al-free ones, while most of the OH-stretching bands shift to higher frequencies in the high temperature range up to ~1100 K

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26

Torri, Rossana. "Barcellona, tra coesione e competizione." TERRITORIO, no. 61 (June 2012): 33–39. http://dx.doi.org/10.3280/tr2012-061005.

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To what extent are European cities today able to nourish a ‘virtu¬ous connection' between economic competitiveness and social cohesion, to prepare urban development strategies to revitalise the economy and urban quality and the struggle against inequal¬ity at the same time? This paper examines the case of Barcelona, which has, since the 1990s, developed a strategy for introducing its image internationally through tourism, culture, and a series of large international events. The progress of Barcelona offers an interesting viewpoint on the processes of interaction between social, cultural and spatial dynamics, and the challenges this poses for the 21st century, in a period in which social inequalities seem to be growing and cities seem to be weakening in their ability to attract and retain younger populations, support the weakest groups, and guarantee minimum conditions of well-being for new migrants.

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27

Mohanty, Paritosh, Yingwei Fei, and Kai Landskron. "Synthesis of Periodic Mesoporous Coesite." Journal of the American Chemical Society 131, no. 28 (July 22, 2009): 9638–39. http://dx.doi.org/10.1021/ja903286m.

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28

Kulik, Eleonora, Norimasa Nishiyama, Yuji Higo, Nico A. Gaida, and Tomoo Katsura. "Hardness of polycrystalline SiO2 coesite." Journal of the American Ceramic Society 102, no. 5 (December 21, 2018): 2251–56. http://dx.doi.org/10.1111/jace.16243.

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29

Mikhailenko, Denis, Alexander Golovin, Andrey Korsakov, Sonja Aulbach, Axel Gerdes, and Alexey Ragozin. "Metasomatic Evolution of Coesite-Bearing Diamondiferous Eclogite from the Udachnaya Kimberlite." Minerals 10, no. 4 (April 24, 2020): 383. http://dx.doi.org/10.3390/min10040383.

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A coesite-bearing diamondiferous eclogite from the Udachnaya kimberlite (Daldyn field, Siberian craton) has been studied to trace its complex evolution recorded in rock-forming and minor mineral constituents. The eclogite sample is composed of rock-forming omphacite (60 vol%), garnet (35 vol%) and quartz/coesite (5 vol%) and contains intergranular euhedral zoned olivine crystals, up to 200 µm long, coexisting with phlogopite, orthopyroxene, clinopyroxene (secondary), K-feldspar, plagioclase, spinel, sodalite and djerfisherite. Garnet grains are zoned, with a relatively homogeneous core and a more magnesian overgrowth rim. The rim zones further differ from the core in having higher Zr/Y (6 times that in the cores), ascribed to interaction with, or precipitation from, a kimberlite-related melt. Judging by pressure-temperature estimates (~1200 °C; 6.2 GPa), the xenolith originated at depths of ~180–200 km at the base of the continental lithosphere. The spatial coexistence of olivine, orthopyroxene and coesite/quartz with K-Na-Cl minerals in the xenolith indicates that eclogite reacted with a deep-seated kimberlite melt. However, Fe-rich olivine, orthopyroxene and low-pressure minerals (sodalite and djerfisherite) likely result from metasomatic reaction at shallower depths during transport of the eclogite by the erupting kimberlite melt. Our results demonstrate that a mixed eclogitic-peridotitic paragenesis, reported previously from inclusions in diamond, can form by interaction of eclogite and a kimberlite-related melt.

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30

Carswell, D. A., R. N. Wilson, and M. Zhai. "Ultra-high pressure aluminous titanites in carbonate-bearing eclogites at Shuanghe in Dabieshan, central China." Mineralogical Magazine 60, no. 400 (June 1996): 461–71. http://dx.doi.org/10.1180/minmag.1996.060.400.07.

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AbstractPetrographic features and compositions of titanites in eclogites within the ultra-high pressure metamorphic terrane in central Dabieshan are documented and phase equilibria and thermobarometric implications discussed. Carbonate-bearing eclogite pods in marble at Shuanghe contain primary metamorphic aluminous titanites, with up to 39 mol.% Ca(Al,Fe3+)FSiO4 component. These titanites formed as part of a coesite-bearing eclogite assemblage and thus provide the first direct petrographic evidence that AlFTi−1O−1 substitution extends the stability of titanite, relative to rutile plus carbonate, to pressures within the coesite stability field. However, it is emphasised that A1 and F contents of such titanites do not provide a simple thermobarometric index of P—T conditions but are constrained by the activity of fluorine, relative to CO2, in metamorphic fluids — as signalled by observations of zoning features in these titanites.These ultra-high pressure titanites show unusual breakdown features developed under more H2O-rich amphibolite-facies conditions during exhumation of these rocks. In some samples aluminous titanites have been replaced by ilmenite plus amphibole symplectites, in others by symplectitic intergrowths of secondary, lower Al and F, titanite plus plagioclase. Most other coesite-bearing eclogite samples in the central Dabieshan terrane contain peak assemblage rutile often partly replaced by grain clusters of secondary titanites with customary low Al and F contents.

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31

Reifenberg, Melina, and Noel W. Thomas. "Ionic network analysis of tectosilicates: the example of coesite at variable pressure." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 74, no. 2 (March 20, 2018): 165–81. http://dx.doi.org/10.1107/s2052520618001312.

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The method of ionic network analysis [Thomas (2017).Acta Cryst.B73, 74–86] is extended to tectosilicates through the example of coesite, the high-pressure polymorph of SiO2. The structural refinements of Černoket al.[Z. Kristallogr.(2014),229, 761–773] are taken as the starting point for applying the method. Its purpose is to predict the unit-cell parameters and atomic coordinates at (p–T–X) values in-between those of diffraction experiments. The essential development step for tectosilicates is to define a pseudocubic parameterization of the O4cages of the SiO4tetrahedra. The six parametersaPC,bPC,cPC, αPC, βPCand γPCallow a full quantification of the tetrahedral structure,i.e.distortion and enclosed volume. Structural predictions for coesite require that two separate quasi-planar networks are defined, one for the silicon ions and the other for the O4cage midpoints. A set of parametric curves is used to describe the evolution with pressure of these networks and the pseudocubic parameters. These are derived by fitting to the crystallographic data. Application of the method to monoclinic feldspars and to quartz and cristobalite is discussed. Further, a novel two-parameter quantification of the degree of tetrahedral distortion is described. At pressures in excess ofca20.45 GPa it is not possible to find a self-consistent solution to the parametric curves for coesite, pointing to the likelihood of a phase transition.

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32

Bruzzo, Aurelio. "La futura politica di coesione dell'U.E.: una ricostruzione del dibattito politico." ARGOMENTI, no. 33 (December 2011): 5–28. http://dx.doi.org/10.3280/arg2011-033001.

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Nell'articolo si effettua una sintetica ricostruzione del dibattito sviluppato in sede politico- istituzionale, durante gli ultimi anni, sulla futura politica di coesione economica, sociale e territoriale che l'Unione europea presumibilmente condurrŕ a partire dal 2014, vale a dire dopo la conclusione dell'attuale periodo di programmazione. Come nelle precedenti occasioni, nel mentre si realizza tale politica, nelle sedi competenti si discute del modo in cui riformare quella successiva, alla luce sia delle conclusioni di una serie di documenti, tra cui un rapporto scientifico, sia dei risultati concretamente ottenuti nell'impiego delle risorse finanziarie stanziate coi fondi strutturali. Infatti, nonostante la grave e preoccupante crisi finanziaria attualmente in corso in alcuni Stati membri, č previsto che nell'autunno di quest'anno la Commissione europea presenti il nuovo pacchetto legislativo sulla politica di coesione 2014-2020.

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33

Lathe, Christian, Monika Koch-Müller, Richard Wirth, Wim Van Westrenen, Hans-Joachim Mueller, Frank Schilling, and Jörn Lauterjung. "The influence of OH in coesite on the kinetics of the coesite-quartz phase transition." American Mineralogist 90, no. 1 (January 2005): 36–43. http://dx.doi.org/10.2138/am.2005.1662.

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34

Ruiz-Cruz, M. D., and C. Sanz de Galdeano. "Diamond and coesite in ultrahigh-pressure–ultrahigh-temperature granulites from Ceuta, Northern Rif, northwest Africa." Mineralogical Magazine 76, no. 3 (June 2012): 683–704. http://dx.doi.org/10.1180/minmag.2012.076.3.17.

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AbstractDiamond and coesite occur in granulites of the Internal Zone of the Rif belt in northwest Africa. Diamond, identified by optical microscopy, electron microprobe analysis, Raman spectroscopy, cathodoluminescence and microstructural electron backscattered diffraction, is present as inclusions up to 20 μm across in garnet, K-feldspar, coesite relics and quartz. Thermobarometric estimates yield P >4.3 GPa and T >1100°C, which corresponds to a depth of formation >150 km. The estimates suggest that the diamond-bearing peridotites and adjacent crustal rocks experienced similar P–T conditions. If this is correct, there is an old (undated) core in the Betic–Rif cordillera and the current models of the tectonic evolution of the area, which are based on 'full Alpine' evolution, must be revised. This discovery provides further valuable information about the complex geotectonic environment of the southeast Spain and north Moroccan collisional orogen.

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35

Palombarini, Giovanni. "Crisi della coesione territoriale e razzismo." QUESTIONE GIUSTIZIA, no. 5 (December 2011): 119–28. http://dx.doi.org/10.3280/qg2011-005010.

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C'č, nel Paese, una diffusa indifferenza rispetto al tema della coesione territoriale e popolare e dei processi di disgregazione messi in atto dalla Lega Nord con una iniziativa politica che o prescinde o č contro la Costituzione e che non esita ad assumere responsabilitŕ nazionali per ottenere risultati funzionali alla rivendicazione etnica. E perň questa indifferenza non potrŕ durare a lungo: quando ci si porrŕ l'esigenza del contrasto all'ormai ventennale declino del Paese il confronto con i princěpi fondamentali della Costituzione non potrŕ essere eluso.

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36

ernok, A., T. B. Ballaran, R. Caracas, N. Miyajima, E. Bykova, V. Prakapenka, H. P. Liermann, and L. Dubrovinsky. "Pressure-induced phase transitions in coesite." American Mineralogist 99, no. 4 (April 1, 2014): 755–63. http://dx.doi.org/10.2138/am.2014.4585.

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37

Mormino, Gianfranco. "Teorie della coesione nell'epistolario Leibniz-Hartsoeker." RIVISTA DI STORIA DELLA FILOSOFIA, no. 4 (December 2016): 215–30. http://dx.doi.org/10.3280/sf2016-004-s1015.

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38

Bardukhinov, L. D., Z. V. Spetsius, and R. V. Monkhorov. "Coesite inclusions in diamonds of Yakutia." Doklady Earth Sciences 470, no. 2 (October 2016): 1059–62. http://dx.doi.org/10.1134/s1028334x16100093.

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39

Koch-Müller, Monika, Przemyslaw Dera, Yingwei Fei, Barry Reno, Nikolai Sobolev, Erik Hauri, and Richard Wysoczanski. "OH−in synthetic and natural coesite." American Mineralogist 88, no. 10 (October 2003): 1436–45. http://dx.doi.org/10.2138/am-2003-1007.

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40

Hemingway, Bruce S., Steven R. Bohlen, W. B. Hankins, Edgar F. Westrum, and Oleg L. Kuskov. "Heat capacity and thermodynamic properties for coesite and jadeite, reexamination of the quartz-coesite equilibrium boundary." American Mineralogist 83, no. 5-6 (June 1, 1998): 409–18. http://dx.doi.org/10.2138/am-1998-5-601.

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41

Gonzalez, Joseph P., Suzanne L. Baldwin, Jay B. Thomas, William O. Nachlas, and Paul G. Fitzgerald. "Evidence for ultrahigh-pressure metamorphism discovered in the Appalachian orogen." Geology 48, no. 10 (June 19, 2020): 947–51. http://dx.doi.org/10.1130/g47507.1.

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Abstract The Appalachian orogen has long been enigmatic because, compared to other parts of the Paleozoic orogens that formed following the subduction of the Iapetus Ocean, direct evidence for ultrahigh-pressure (UHP) metamorphism has never been found. We report the first discovery of coesite in the Appalachian orogen in a metapelite from the mid-Ordovician (Taconic orogeny) Tillotson Peak Complex in Vermont (USA). Relict coesite occurs within a bimineralic SiO2 inclusion in garnet. In situ elastic barometry and trace-element thermometry allow reconstruction of the garnet growth history during prograde metamorphism. The data are interpreted to indicate garnet nucleation and crystallization during blueschist- to eclogite-facies subduction zone metamorphism, followed by garnet rim growth at UHP conditions of > 28 kbar and > 530 ° C. Results provide the first direct evidence that rocks of the Appalachian orogen underwent UHP metamorphism to depths of > 75 km and warrant future studies that constrain the extent of UHP metamorphism.

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42

Woodland, Alan B., Andrei V. Girnis, Vadim K. Bulatov, Gerhard P. Brey, and Heidi E. Höfer. "Breyite inclusions in diamond: experimental evidence for possible dual origin." European Journal of Mineralogy 32, no. 1 (February 11, 2020): 171–85. http://dx.doi.org/10.5194/ejm-32-171-2020.

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Abstract. Inclusions of breyite (previously known as walstromite-structured CaSiO3) in diamond are usually interpreted as retrogressed CaSiO3 perovskite trapped in the transition zone or the lower mantle. However, the thermodynamic stability field of breyite does not preclude its crystallization together with diamond under upper-mantle conditions (6–10 GPa). The possibility of breyite forming in subducted sedimentary material through the reaction CaCO3 + SiO2 = CaSiO3 + C + O2 was experimentally evaluated in the CaO–SiO2–C–O2 ± H2O system at 6–10 GPa, 900–1500 ∘C and oxygen fugacity 0.5–1.0 log units below the Fe–FeO (IW) buffer. One experimental series was conducted in the anhydrous subsystem and aimed at determining the melting temperature of the aragonite–coesite (or stishovite) assemblage. It was found that melting occurs at a lower temperature (∼1500 ∘C) than the decarbonation reaction, which indicates that breyite cannot be formed from aragonite and silica under anhydrous conditions and an oxygen fugacity above IW – 1. In the second experimental series, we investigated partial melting of an aragonite–coesite mixture under hydrous conditions at the same pressures and redox conditions. The melting temperature in the presence of water decreased strongly (to 900–1200 ∘C), and the melt had a hydrous silicate composition. The reduction of melt resulted in graphite crystallization in equilibrium with titanite-structured CaSi2O5 and breyite at ∼1000 ∘C. The maximum pressure of possible breyite formation is limited by the reaction CaSiO3 + SiO2 = CaSi2O5 at ∼8 GPa. Based on the experimental results, it is concluded that breyite inclusions found in natural diamond may be formed from an aragonite–coesite assemblage or carbonate melt at 6–8 GPa via reduction at high water activity.

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43

MUKHERJEE, BARUN K., and HIMANSHU K. SACHAN. "Fluids in coesite-bearing rocks of the Tso Morari Complex, NW Himalaya: evidence for entrapment during peak metamorphism and subsequent uplift." Geological Magazine 146, no. 6 (July 15, 2009): 876–89. http://dx.doi.org/10.1017/s0016756809990069.

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AbstractFluid inclusions trapped in coesite-bearing rocks provide important information on the fluid phases present during ultrahigh-pressure metamorphism. The subduction-related coesite-bearing eclogites of the Tso Morari Complex, Himalaya, contain five major types of fluids identified by microthermometry and Raman spectroscopy. These are: (1) high-salinity brine, (2) N2, (3) CH4, (4) CO2and (5) low-salinity aqueous fluids. These fluids were trapped during both deep subduction and exhumation processes. The coesite-bearing rocks are inferred to have been buried to a depth of >120 km, where they experienced ultrahigh-pressure metamorphism. The fluid–rock interaction provides direct evidence for fluid derivation during a deep subduction process as demonstrated by silica–carbonate assemblages in eclogite. High salinity brine, N2and CH4inclusions are remnants of prograde and peak metamorphic fluids, whereas CO2and low-salinity aqueous fluids appear to have been trapped late, during uplift. The high-salinity brine was possibly derived from subducted ancient metasedimentary rocks, whereas the N2and CH4fluids were likely generated through chemical breakdown of NH3-bearing K minerals and graphite. Alternatively, CH4might have been formed by a mixed fluid that was released from calcareous sediments during subduction or supplied through subducted oceanic metabasic rocks. High density CO2is associated with matrix minerals formed during granulite-facies overprinting of the ultrahigh-pressure eclogite. During retrogression to amphibolite-facies conditions, low-salinity fluids were introduced from external sources, probably the enclosing gneisses. This source enhances salinity differences as compared to primary saline inclusions. The subducting Indian lithosphere produced brines prior to achieving maximal depths of >120 km, where fluids were instead dominated by gaseous phases. Subsequently, the Indian lithosphere released CO2-rich fluids during fast exhumation and was then infiltrated by the low-salinity aqueous fluids near the surface through external sources. Elemental modelling may improve quantitative understanding of the complexity of fluids and their reactions.

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44

Buoniconto, Alfonsina. "SCOMPORRE E RICOMPORRE: INSEGNARE LA COESIONE PER INSEGNARE LA COMPRENSIONE." Italiano LinguaDue 14, no. 1 (July 26, 2022): 448–70. http://dx.doi.org/10.54103/2037-3597/18297.

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Questo contributo si propone di indagare l’impatto che il corretto o mancato riconoscimento delle funzioni dei meccanismi di coesione testuale ha sul processo di comprensione dei testi funzionali scritti. I risultati restituiti dall’analisi quantitativa e qualitativa dei dati relativi alle prestazioni di studenti e studentesse del biennio della scuola secondaria di secondo grado nelle prove di lettura e comprensione sembrano confermare l’esistenza di una correlazione tra il corretto esito dei questionari di comprensione e la corretta identificazione dei meccanismi di coesione sollecitata negli stessi questionari. Decomposing and recomposing: teaching cohesion to teach understanding This paper aims to investigate the impact that the correct or lack of recognition of the functions of textual cohesion mechanisms has on the process of comprehension of functional written texts. The results obtained through quantitative and qualitative data analysis on the performance of high school students (first and second year) in reading comprehension tests seem to confirm the existence of a correlation between the correct completion of comprehension questionnaires and the correct identification of cohesion mechanisms in the very same questionnaires.

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45

Howie, A., and D. W. McComb. "Valence electron spectroscopy of inhomogeneous media." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1150–51. http://dx.doi.org/10.1017/s0424820100130389.

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The bulk loss function Im(-l/ε (ω)), a well established tool for the interpretation of valence loss spectra, is being progressively adapted to the wide variety of inhomogeneous samples of interest to the electron microscopist. Proportionality between n, the local valence electron density, and ε-1 (Sellmeyer's equation) has sometimes been assumed but may not be valid even in homogeneous samples. Figs. 1 and 2 show the experimentally measured bulk loss functions for three pure silicates of different specific gravity ρ - quartz (ρ = 2.66), coesite (ρ = 2.93) and a zeolite (ρ = 1.79). Clearly, despite the substantial differences in density, the shift of the prominent loss peak is very small and far less than that predicted by scaling e for quartz with Sellmeyer's equation or even the somewhat smaller shift given by the Clausius-Mossotti (CM) relation which assumes proportionality between n (or ρ in this case) and (ε - 1)/(ε + 2). Both theories overestimate the rise in the peak height for coesite and underestimate the increase at high energies.

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46

Idrissi, Hosni, Patrick Cordier, Damien Jacob, and Nicolas Walte. "Dislocations and plasticity of experimentally deformed coesite." European Journal of Mineralogy 20, no. 4 (August 29, 2008): 665–71. http://dx.doi.org/10.1127/0935-1221/2008/0020-1849.

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47

Deon, Fiorenza, Monika Hövelmann Koch-Müller, and Sylvia-Monique Thomas. "Coupled boron and hydrogen incorporation in coesite." European Journal of Mineralogy 21, no. 1 (February 6, 2009): 9–16. http://dx.doi.org/10.1127/0935-1221/2009/0021-1843.

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48

Taguchi, Tomoki, Yui Kouketsu, Yohei Igami, Tomoyuki Kobayashi, and Akira Miyake. "Hidden intact coesite in deeply subducted rocks." Earth and Planetary Science Letters 558 (March 2021): 116763. http://dx.doi.org/10.1016/j.epsl.2021.116763.

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49

Olagnero, Manuela. "Prove di coesione sociale in contesti urbani." PSICOLOGIA DI COMUNITA', no. 2 (March 2013): 35–46. http://dx.doi.org/10.3280/psc2012-002004.

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50

Miyahara, M., E. Ohtani, A. Yamaguchi, S. Ozawa, T. Sakai, and N. Hirao. "Discovery of coesite and stishovite in eucrite." Proceedings of the National Academy of Sciences 111, no. 30 (July 15, 2014): 10939–42. http://dx.doi.org/10.1073/pnas.1404247111.

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