Structural role of copper in the minerals of the pearceite-polybasite group: the case of the new minerals cupropearceite and cupropolybasite

2007 ◽  
Vol 71 (06) ◽  
pp. 641-650 ◽  
Author(s):  
L. Bindi ◽  
M. Evain ◽  
P. G. Spry ◽  
K. T. Tait ◽  
S. Menchetti
Keyword(s):  
Chemical Characterization ◽  
Sample Space ◽  
The Other ◽  
Crystal Chemical ◽  
Structural Position ◽  
Space Group ◽  
Cu Content ◽  
Own Name

Abstract The pearceite-polybasite group of minerals, general formula [M6T2S7][Ag9CuS4] with M = Ag, Cu; and T = As, Sb, show a crystal structure which can be described as the succession, along the c axis, of two pseudo-layer modules: a [M6T2S7]2– A module layer and a [Ag9CuS4]2+ B module layer. Copper is present in one structural position of the B module layer and replaces Ag in the only fully occupied M position of the A module layer. When the Cu content is >4.00 a.p.f.u., the structural position of the A module layer becomes Cu-dominant and, consequently, the mineral deserves its own name. In this paper we report the crystal-chemical characterization of two Cu-rich members exhibiting the 111 unitcell type (corresponding to the Tac polytype). One sample (space group (P )m1, a 7.3218(8), c 11.8877(13) Å, V 551.90(10) Å3, Z = 1) having As >Sb and with the structural position of the A module layer dominated by Cu, has been named cupropearceite and the other sample (space group (P3̄)m1, a 7.3277(3), c 11.7752(6) Å, V 547.56(8) Å3, Z = 1) having Sb >As has been named cupropolybasite. Both the new minerals and mineral names have been approved by the IMA-CNMNC.

scholarly journals Self-referential false associations: A self-enhanced constructive effect for verbal but not pictorial stimuli

2021 ◽  
pp. 174702182110097
Author(s):  
Jianqin Wang ◽  
Henry Otgaar ◽  
Mark L Howe ◽  
Sen Cheng
Keyword(s):  
Episodic Memory ◽  
The Self ◽  
The Other ◽  
Reference Condition ◽  
Spreading Activation ◽  
Critical Lure ◽  
Picture Stimuli ◽  
Own Name ◽  
Self Reference

Memory is considered to be a flexible and reconstructive system. However, there is little experimental evidence demonstrating how associations are falsely constructed in memory, and even less is known about the role of the self in memory construction. We investigated whether false associations involving non-presented stimuli can be constructed in episodic memory and whether the self plays a role in such memory construction. In two experiments, we paired participants’ own names (i.e., self-reference) or the name “Adele” (i.e., other-reference) with words and pictures from Deese/Roediger–McDermott (DRM) lists. We found that (1) participants not only falsely remembered the non-presented lure words and pictures as having been presented, but also misremembered that they were paired with their own name or “Adele,” depending on the referenced person of related DRM lists; and (2) there were more critical lure–self associations constructed in the self-reference condition than critical lure–other associations in the other-reference condition for word but not for picture stimuli. These results suggest a self-enhanced constructive effect that might be driven by both relational and item-specific processing. Our results support the spreading-activation account for constructive episodic memory.

Fine-grained weathering products in waste disposal from two sulphide mines in the northern Apennines, Italy

Clay Minerals ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 423-433 ◽  
Author(s):  
E. Dinelli ◽  
N. Morandi ◽  
F. Tateo
Keyword(s):  
Acidic Solution ◽  
Chemical Characterization ◽  
Northern Apennines ◽  
The Other ◽  
Blue Colour ◽  
Fine Grained ◽  
Surrounding Environment ◽  
Waste Rock Piles ◽  
Cu And Zn

AbstractFrom mineralogical and chemical characterization of two waste-rock piles from Vigonzano and Libiola sulphide mines in the northern Apennines, two types of fine-grained weathering products were recognized, One, from the Vigonzano mine, has a typical blue colour and consists of the Cu-Al sulphate of the woodwardite group. Its formation is related to an alkaline geochemical barrier, it is rather stable in acidic solution, and it controls Cu and Zn dispersion in the surrounding environment. The other group of sediments has a typical ochreous colour. Vigonzano samples consist mostly of goethite, whereas ferrihydrite is abundant in the Libiola sample. The ochreous sediments are enriched in Co, As, Mo, Se and Mn, thus significantly reducing the potential environmental hazard of the site, whereas solubility tests indicated possible problems due to AI dissolution at Libiola.

The Role of Temperature on Hydration of Binary System of Metakaolin/Portland Cement

2016 ◽  
Vol 851 ◽  
pp. 51-56 ◽  
Author(s):  
Martin Boháč ◽  
Radoslav Novotný ◽  
Jakub Tkacz ◽  
Miroslava Hajdúchová ◽  
Martin Palou ◽  
...  
Keyword(s):  
Binary System ◽  
Portland Cement ◽  
Isothermal Calorimetry ◽  
Chemical Characterization ◽  
Exothermic Peak ◽  
Early Hydration ◽  
Different Temperatures ◽  
C 50

The role of temperature of metakaolin/Portland cement binary system was studied by isothermal calorimetry. Sample with 50 % of metakaolin replacement were monitored at 30 °C, 40 °C, 50 °C and 60 °C. Structural and chemical characterization of hardened pastes was obtained by scanning electron and Raman microscopy. Paper deals with kinetics of main exothermal reactions during early hydration of the system. Activation energies were calculated for processes related to each exothermic peak. The nature of hydration products at different temperatures was revealed by microstructural studies.

scholarly journals Ontology, Ontologies and the “I” of FAIR

2020 ◽  
Vol 2 (1-2) ◽  
pp. 181-191 ◽  
Author(s):  
Giancarlo Guizzardi
Keyword(s):  
Value Of Information ◽  
Direct Consequence ◽  
Semantic Interoperability ◽  
The Other ◽  
Added Value ◽  
Computational Tools ◽  
Other Hand ◽  
Guiding Principles

According to the FAIR guiding principles, one of the central attributes for maximizing the added value of information artifacts is interoperability. In this paper, I discuss the importance, and propose a characterization of the notion of Semantic Interoperability. Moreover, I show that a direct consequence of this view is that Semantic Interoperability cannot be achieved without the support of, on one hand, (i) ontologies, as meaning contracts capturing the conceptualizations represented in information artifacts and, on the other hand, of (ii) Ontology, as a discipline proposing formal meth- ods and theories for clarifying these conceptualizations and articulating their representations. In particular, I discuss the fundamental role of formal ontological theories (in the latter sense) to properly ground the construction of representation languages, as well as methodological and computational tools for supporting the engineering of ontologies (in the former sense) in the context of FAIR.

Histolocalization and physico-chemical characterization of dihydrochalcones: Insight into the role of apple major flavonoids

2013 ◽  
Vol 90 ◽  
pp. 78-89 ◽  
Author(s):  
Matthieu Gaucher ◽  
Thomas Dugé de Bernonville ◽  
David Lohou ◽  
Sylvain Guyot ◽  
Thomas Guillemette ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Physico Chemical ◽  
Insight Into

scholarly journals Characterization of DNA methylation as a function of biological complexity via dinucleotide inter-distances

2016 ◽  
Vol 374 (2063) ◽  
pp. 20150227 ◽  
Author(s):  
Giulia Paci ◽  
Giampaolo Cristadoro ◽  
Barbara Monti ◽  
Marco Lenci ◽  
Mirko Degli Esposti ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Statistical Study ◽  
The Other ◽  
Biological Complexity ◽  
Functional Roles ◽  
Exponential Tails ◽  
Cg Dinucleotide ◽  
Cg Dinucleotides

We perform a statistical study of the distances between successive occurrences of a given dinucleotide in the DNA sequence for a number of organisms of different complexity. Our analysis highlights peculiar features of the CG dinucleotide distribution in mammalian DNA, pointing towards a connection with the role of such dinucleotide in DNA methylation. While the CG distributions of mammals exhibit exponential tails with comparable parameters, the picture for the other organisms studied (e.g. fish, insects, bacteria and viruses) is more heterogeneous, possibly because in these organisms DNA methylation has different functional roles. Our analysis suggests that the distribution of the distances between CG dinucleotides provides useful insights into characterizing and classifying organisms in terms of methylation functionalities.

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