scholarly journals Genesis and stability of accessory phosphates in silicic magmatic rocks: a Western Carpathian case study

Mineralogia ◽  
2008 ◽  
Vol 39 (1-2) ◽  
pp. 53-66 ◽  
Author(s):  
Igor Broska ◽  
Igor Petrík

Genesis and stability of accessory phosphates in silicic magmatic rocks: a Western Carpathian case studyThe formation of accessory phosphates in granites reflects many chemical and physical factors, including magma composition, oxidation state, concentrations of volatiles and degree of differentiation. The geotectonic setting of granites can be judged from the distribution and character of their phosphates. Robust apatite crystallization is typical of the early magmatic crystallization of I-type granitoids, and of late magmatic stages when increased Ca activity may occur due to the release of anorthite from plagioclase. Although S-type granites also accumulate apatite in the early stages, increasing phosphorus in late differentiates is common due to their high ASI. The apatite from the S-types is enriched in Mn compared to that in I-type granites. A-type granites characteristically contain minor amounts of apatite due to low P concentrations in their magmas. Monazite is typical of S-type granites but it can also become stable in late I-type differentiates. Huttonite contents in monazite correlate roughly positively with temperature. The cheralite molecule seems to be highest in monazite from the most evolved granites enriched in B and F. Magmatic xenotime is common mainly in the S-type granites, but crystallization of secondary xenotime is not uncommon. The formation of the berlinite molecule in feldspars in peraluminous melts may suppress phosphate precipitation and lead to distributional inhomogeneities. Phosphate mobility commonly leads to the formation of phosphate veinlets in and outside granite bodies. The stability of phosphates in the superimposed, metamorphic processes is restricted. Both monazite-(Ce) and xenotime-(Y) are unstable during fluid-activated overprinting. REE accessories, especially monazite and allanite, show complex replacement patterns culminating in late allanite and epidote formation.

Author(s):  
Camilo POTOCNJAK-OXMAN

Stir was a crowd-voted grants platform aimed at supporting creative youth in the early stages of an entrepreneurial journey. Developed through an in-depth, collaborative design process, between 2015 and 2018 it received close to two hundred projects and distributed over fifty grants to emerging creatives and became one of the most impactful programs aimed at increasing entrepreneurial activity in Canberra, Australia. The following case study will provide an overview of the methodology and process used by the design team in conceiving and developing this platform, highlighting how the community’s interests and competencies were embedded in the project itself. The case provides insights for people leading collaborative design processes, with specific emphasis on some of the characteristics on programs targeting creative youth


2005 ◽  
Vol 11 (1) ◽  
pp. 187-204 ◽  
Author(s):  
David Skidmore ◽  
Jan Marston ◽  
Gretchen Olson

The idea that international perspectives should be represented throughout the curriculum lies at the heart of the American Council on Education’s “Global Learning for All” initiative, which asserts that: “…international and global learning is important for all students—not just an elite few—and should be integral to every degree program." Drake University’s own internationalization program, still in its early stages, combines a number of elements that fit its particular needs as a medium-sized (approximately 3,000 undergraduates), private, comprehensive university located in the Midwest. 


Author(s):  
A.C.C. Coolen ◽  
A. Annibale ◽  
E.S. Roberts

This chapter reviews graph generation techniques in the context of applications. The first case study is power grids, where proposed strategies to prevent blackouts have been tested on tailored random graphs. The second case study is in social networks. Applications of random graphs to social networks are extremely wide ranging – the particular aspect looked at here is modelling the spread of disease on a social network – and how a particular construction based on projecting from a bipartite graph successfully captures some of the clustering observed in real social networks. The third case study is on null models of food webs, discussing the specific constraints relevant to this application, and the topological features which may contribute to the stability of an ecosystem. The final case study is taken from molecular biology, discussing the importance of unbiased graph sampling when considering if motifs are over-represented in a protein–protein interaction network.


Author(s):  
Hyojin Kim ◽  
Daesik Hur ◽  
Tobias Schoenherr

Supplier development has been a critical supply management practice since the 1990s. In many instances, it has even become imperative for buyer firms to support and prepare their supply bases for uncertain economic and market environments, socially and environmentally conscious customers, advances in digital technologies, and increasing competition. Yet, research that approaches supplier development with the objective to advance all these dimensions in an integrated fashion is scarce. This study fills this void by exploring how a buyer firm may address these emerging challenges in its supply base. Specifically, an in-depth case study of LG Electronics explores how the firm designs and operates multidimensional supplier development activities to foster the stability and sustainability of its supply base while enhancing its core suppliers’ competitive capabilities. This chapter illustrates how supplier development can be taken to the next level, presents implications for managerial practice, and outlines promising future research avenues.


2021 ◽  
pp. 154134462199624
Author(s):  
Felix Okechukwu Dike ◽  
JohnBosco Chika Chukwuorji

The theory of transformative learning (TL) has been criticized secondhand for its lack of clarity in capturing and explaining in detail the processes undergone by learners who are going through TL experiences and their link to learning outcomes. Using a case study design, and carefully synthesized TL processes (TLPs) from Mezirow’s TL theory, we present—moment by moment—the TLPs linked to outcomes identified among a group of teachers who participated in a values-based workshop. Participants were followed through interviews for over 72 weeks to trace the stability of their TL outcome. TL processes identified were compared to Mezirow’s 10 processes. The article discusses ontological transformations gained and offers fresh perspective to identifying TLPs that can be linked to outcomes.


2021 ◽  
Vol 1 ◽  
pp. 3159-3168
Author(s):  
Sohail Ahmed Soomro ◽  
Yazan A M Barhoush ◽  
Zhengya Gong ◽  
Panos Kostakos ◽  
Georgi V. Georgiev

AbstractPrototyping is an essential activity in the early stages of product development. This activity can provide insight into the learning process that takes place during the implementation of an idea. It can also help to improve the design of a product. This information and the process are useful in design education as they can be used to enhance students' ability to prototype their ideas and develop creative solutions. To observe the activity of prototype development, we conducted a study on students participating in a 7-week course: Principles of Digital Fabrication. During the course, eight teams made prototypes and shared their weekly developments via internet blog posts. The posts contained prototype pictures, descriptions of their ideas, and reflections on activities. The blog documentation of the prototypes developed by the students was done without the researchers' intervention, providing essential data or research. Based on a review of other methods of capturing the prototype development process, we compare existing documentation tools with the method used in the case study and outline the practices and tools related to the effective documentation of prototyping activity.


2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Osama A. B. Hassan

Abstract This study investigates the stability of timber members subjected to simultaneously acting axial compression and bending moment, with possible risk for torsional and flexural–torsional buckling. This situation can occur in laterally supported members where one side of the member is braced but the other side is unbraced. In this case, the free side will buckle out of plane while the braced side will be prevented from torsional and flexural–torsional buckling. This problem can be evident for long members in timber-frame structures, which are subjected to high axial compression combined with bending moments in which the member is not sufficiently braced at both sides. This study is based on the design requirement stated in Eurocode 5. Solution methods discussed in this paper can be of interest within the framework of structural and building Engineering practices and education in which the stability of structural elements is investigated. Article Highlights This case study investigates some design situations where the timber member is not sufficiently braced. In this case, a stability problem associated with combined torsional buckling and flexural buckling can arise. The study shows that the torsional and/or flexural–torsional buckling of timber members can be important to control in order to fulfil the criteria of the stability of the member according to Eurocode 5 and help the structural engineer to achieve safer designs. The study investigates also a simplified solution to check the effect of flexural torsional buckling of laterally braced timber members.


Author(s):  
Przemysław Banasik ◽  
Katarzyna Metelska-Szaniawska ◽  
Małgorzata Godlewska ◽  
Sylwia Morawska

AbstractThe goal of this paper is to identify factors which affect judges’ productivity and career choice motives with the view of increasing judicial efficiency. Specifically, the investigation focuses on such aspects as judges’ remuneration, promotion, threat of judgment revocation, service/mission, periodic assessment, the threat of a complaint about protracted proceedings or of disciplinary proceedings, the threat of destabilization of the employment relationship, status/prestige of the profession, power/authority, social recognition, leisure, as well as administrative supervision and self-monitoring. To this end, a survey was conducted among judges of three of the largest Polish regional courts and subordinate district courts. The descriptive and statistical analyses show that judges’ care for the number of cases resolved, proxying for their productivity, is significantly correlated with self-monitoring of their adjudication activity. The stability of employment, the status/prestige of the profession and a relatively high remuneration are the most important factors in terms of judges’ career choices. In their care for the number of cases resolved remuneration is, albeit, no longer a relevant factor. Judges monitor their productivity due to reasons other than remuneration, possibly the sense of service/mission and the threat of various adverse consequences, the evidence for which is, however, also rather weak.


2019 ◽  
Vol 19 (10) ◽  
pp. 2079-2095 ◽  
Author(s):  
Michele Perrotti ◽  
Piernicola Lollino ◽  
Nunzio Luciano Fazio ◽  
Mario Parise

Abstract. The stability of man-made underground cavities in soft rocks interacting with overlying structures and infrastructures represents a challenging problem to be faced. Based upon the results of a large number of parametric two-dimensional (2-D) finite-element analyses of ideal cases of underground cavities, accounting for the variability both cave geometrical features and rock mechanical properties, specific charts have been recently proposed in the literature to assess at a preliminary stage the stability of the cavities. The purpose of the present paper is to validate the efficacy of the stability charts through the application to several case studies of underground cavities, considering both quarries collapsed in the past and quarries still stable. The stability graphs proposed by Perrotti et al. (2018) can be useful to evaluate, in a preliminary way, a safety margin for cavities that have not reached failure and to detect indications of predisposition to local or general instability phenomena. Alternatively, for sinkholes that already occurred, the graphs may be useful in identifying the conditions that led to the collapse, highlighting the importance of some structural elements (as pillars and internal walls) on the overall stability of the quarry system.


Sign in / Sign up

Export Citation Format

Share Document