scholarly journals Practical hints and tips for solution of pseudo-merohedric twins: three case studies

2021 ◽  
Vol 77 (5) ◽  
pp. 452-465
Author(s):  
S. R. Parkin
Keyword(s):  
Case Studies ◽  
Small Molecule ◽  
Worked Examples ◽  
Common Phenomenon ◽  
Group Setting ◽  
Higher Symmetry ◽  
Volume Fractions ◽  
The Third ◽  
Structure Solution ◽  
Two Component

Twinning by pseudo-merohedry is a common phenomenon in small-molecule crystallography. In cases where twin-component volume fractions are markedly different, structure solution is often no more difficult than for non-twinned structures of similar complexity. When twin-component volume fractions are similar, however, structure solution can be much more of a problem. This paper presents hints and tips for such cases by means of three worked examples. The first example presents the most common (and simplest) case of a two-component pseudo-orthorhombic twin. The second example describes structure solution of a reticular threefold pseudo-hexagonal twin that benefits from use of an unconventional space-group setting. The third example covers structure solution of a reticular fourfold pseudo-tetragonal twin. All three structures are ultimately shown to be monoclinic crystals that twin as a consequence of unit-cell metrics that mimic those of higher symmetry crystal systems.

NEW TECHNOLOGIES AND PRACTICES FOR WASTE MINIMIZATION IN THE CHEMICAL AND PETROCHEMICAL INDUSTRIES : FINDINGS OF THE SALVADOR, BRAZIL, 1993 CONFERENCE

1994 ◽  
Vol 30 (3) ◽  
pp. 1-9
Author(s):  
Francisco Fontes Lima ◽  
Francisco Alves Pereira
Keyword(s):  
Waste Management ◽  
Environmental Protection ◽  
Case Studies ◽  
New Technologies ◽  
Waste Minimization ◽  
Source Control ◽  
International Conference ◽  
The Third ◽  
Control Programmes ◽  
Petrochemical Industries

This paper describes the findings of the “Third International Conference on Waste Management in the Chemical and Petrochemical Industries,” held in Salvador, Brazil, October 20-23, 1993. A summary of the 74 technical papers, divided into six major categories, is presented together with comments on the more stringent legislation concerning source control programmes. Case studies of two large chemical complexes that have been developing successful waste minimization programmes are described in detail: CETREL-Environmental Protection Company in Camaçari, Brazil, and BASF AG in Ludwigshafen, Germany.

Conclusion

2018 ◽  
Author(s):  
John West
Keyword(s):  
Eighteenth Century ◽  
Case Studies ◽  
Literary History ◽  
The Political ◽  
The Third ◽  
Religious Differences

Literary history often positions Dryden as the precursor to the great Tory satirists of the eighteenth century, like Pope and Swift. Yet a surprising number of Whig writers expressed deep admiration for Dryden, despite their political and religious differences. They were particularly drawn to the enthusiastic dimensions of his writing. After a short reading of Dryden’s poem to his younger Whig contemporary William Congreve, this concluding chapter presents three case studies of Whig writers who used Dryden to develop their own ideas of enthusiastic literature. These three writers are Elizabeth Singer Rowe, John Dennis, and the Third Earl of Shaftesbury. These case studies are used to critique the political polarizations of seventeenth- and eighteenth-century literary history and to stress instead how literary friendship crossed political allegiances, and how writers of differing ideological positions competed to control mutually appealing ideas and vocabularies.

Practical Truth

2018 ◽  
Author(s):  
David Charles
Keyword(s):  
Nicomachean Ethics ◽  
Third Way ◽  
The Third ◽  
Two Component ◽  
Major Competitor ◽  
Additional Support

This paper concerns Aristotle’s discussion of practical truth in Nicomachean Ethics VI.2.1139a17–b5. The essay falls into five sections. In the first three, I outline two styles of interpretation of Aristotle’s remarks and suggest that one of them (which I call ‘the third way’) gives a better reading than that offered by its major competitor (which I call ‘the two-component’ view). In the fourth I consider some texts in the remainder of NE VI which provide additional support for the third way of reading. In a brief concluding section, I seek to locate Aristotle’s view of practical truth, so understood, in a broader philosophical context.

scholarly journals The Effects of Molecular Packing Behavior of Small-Molecule Acceptors in Ternary Organic Solar Cells

2021 ◽  
Vol 11 (2) ◽  
pp. 755
Author(s):  
Eunhee Lim
Keyword(s):  
Solar Cells ◽  
Energy Level ◽  
Ternary System ◽  
Small Molecule ◽  
Organic Solar Cells ◽  
Orbital Energy ◽  
Working Mechanism ◽  
Energy Level Structure ◽  
The Third ◽  
Molecular Backbone

Herein, two diketopyrrolopyrrole (DPP)-based, small-molecule isomers, o- and p-DPP-PhCN, were introduced as acceptors in ternary organic solar cells (OSCs). The isomers have the same molecular backbone but differ in the positions of the cyanide (CN) substituents (ortho and para), which greatly affects their packing behavior. Ternary solar cells composed of poly(3-hexylthiophene) (P3HT):DPP-PhCN:phenyl-C61-butyric acid methyl ester (PCBM) were fabricated, and the effects of the different packing behaviors of the third component on the device performance and the working mechanism of the ternary cells were investigated. The addition of o-DPP-PhCN with a relatively high-lying lowest unoccupied molecular orbital energy level resulted in an increase in the open-circuit voltage (VOC) in the ternary devices, demonstrating the alloy-like structure of the two acceptors (o-DPP-PhCN and PCBM) in the ternary system. However, the p-DPP-PhCN-based ternary cells exhibited VOC values similar to that of a P3HT:PCBM binary cell, irrespective of the addition of p-DPP-PhCN, indicating a cascade energy-level structure in the ternary system and an effective charge transfer from the P3HT to the PCBM. Importantly, by increasing the addition of p-DPP-PhCN, the short-circuit current density increased substantially, resulting in pronounced shoulder peaks in the external quantum efficiency responses in the long-wavelength region, corresponding to the contribution of the photocurrent generated by the light absorption of p-DPP-PhCN. Despite sharing the same molecular backbone, the two DPP-PhCNs exhibited substantially different packing behaviors according to the position of their CN substituents, which also greatly affected the working mechanism of the ternary devices fabricated using the DPP-PhCNs as the third component.

A Social Sonic Paradigm

2021 ◽  
pp. 540-554
Author(s):  
Tegan Bristow ◽  
João Orecchia Zúñiga
Keyword(s):  
Case Studies ◽  
Southern Africa ◽  
Political Engagement ◽  
Sound Art ◽  
Intellectual Engagement ◽  
The Third ◽  
Primary Focus ◽  
Definition Of ◽  
Forms Of Knowledge

This chapter presents an examination of why—in contemporary Africa, with Southern Africa as the primary focus—there are very few artists working with sound in a manner that fits the paradigm of sound art as it is known in Euro-America. Emphasis is not placed on a lack of intellectual engagement, which is significant in the Euro-American definition of sound art. What is presented does not aim to deviate from this, but rather acts to affirm an engagement with alternative forms of knowledge and mechanisms of sound found in the South. Three areas are explored; these however are interlinked and do not stand alone. The first is an understanding of the practice of interdisciplinarity as political engagement. The second explores the role of community and communal interaction with sound and how this is fundamental to form in the region. The third extends this by showing how the histories of knowledge and power are fundamental to these explorations in the region, emphasizing how contemporary explorations of sound are used to both contain and shift these histories. The chapter takes shape with the use of case studies and draws on interviews conducted by the authors.

scholarly journals Public and Private Ownership in the Iranian Constitution: Principle 44, A Barrier for Development

2017 ◽  
Vol 10 (4) ◽  
pp. 73
Author(s):  
Ahmad Torabi
Keyword(s):  
Case Studies ◽  
Economic Impacts ◽  
Private Ownership ◽  
Public Ownership ◽  
Public And Private ◽  
The Third ◽  
Public Property ◽  
Legal Challenges ◽  
The Law ◽  
The Government

The Iranian legislator has sought to protect public property and public ownership in the Iranian Constitution in accordance with Islamic principles, terms and procedures. There are a number of principles that have been directly applied to this purpose; however, one principle has had a very significant impact on government domination of the economy of Iran: principle 44. This principle does not directly describe public property; rather, it aims to determine the areas that are under public ownership and are administered by the government. However, the principle has some contradictions and legal challenges in itself. In addition, the supplementary law that has been enacted to provide the areas for the enforcement of principle 44 fails to secure the aims of the legislator. Therefore, this paper analyses legal challenges of the principle, as well as its supplementary law, and gives suggestions to solve the challenges.This paper is divided into four sections. The first section provides an analysis of the principle itself, and its relationship and consistency with other principles of the constitution. In the second section, the Law of Implementation of Principle 44 and the legal challenges that arise from it will be discussed. The third section focuses on the negative economic impacts of this law, as well as case studies of it. Lastly, the paper provides a summary of suggestions to amend this law.

Naturalized Aesthetics and Emotion Theory

Projections ◽  
2018 ◽  
Vol 12 (2) ◽  
pp. 76-85 ◽  
Author(s):  
Rainer Reisenzein
Keyword(s):  
Empirical Evidence ◽  
Case Studies ◽  
Integrated System ◽  
Third Culture ◽  
Extended Version ◽  
Basic Emotions ◽  
The Third ◽  
Psychological Theories ◽  
Concrete Application ◽  
Emotion Theory

Murray Smith’s proposal in Film, Art, and the Third Culture for a naturalized aesthetics is of interest to both film theorists and psychologists: for the former, it helps to elucidate how films work; for the latter, it provides concrete application cases of psychological theories. However, there are reasons for believing that the theory of emotions that Smith has adopted from psychology to ground his case studies—an extended version of basic emotions theory—is less well supported than he suggests. The available empirical evidence seems more compatible with the assumption that the different emotions are outputs of a single, integrated system.

An Improved Triple-Tandem Organic Solar Cell

2009 ◽  
Vol 1212 ◽  
Author(s):  
Dewei Zhao ◽  
Xiao Wei Sun ◽  
Lin Ke ◽  
Swee Tiam Tan
Keyword(s):  
Solar Cell ◽  
Small Molecule ◽  
Organic Solar Cells ◽  
Organic Solar Cell ◽  
Copper Phthalocyanine ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Open Circuit ◽  
Solar Irradiation ◽  
The Third

AbstractWe present an efficient polymer-small molecule triple-tandem organic solar cell (OSC), consisting of poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) bulk heterojunction as the first and second cells, and small molecules copper phthalocyanine (CuPc) and fullerene (C60) as the third cell on top. These sub-cells are connected by an intermediate layer of Al(1 nm)/MoO3(15 nm), which appears to be highly transparent, structurally smooth, and electrically functional. Compared to our previous all polymer triple-tandem organic solar cells (2.03%), this polymer-small molecule triple-tandem organic solar cell achieves an improved power conversion efficiency of 2.18% with a short-circuit current density (Jsc) = 3.02 mA/cm2, open-circuit voltage (Voc) = 1.51 V, and fill factor (FF) = 47.7% under simulated solar irradiation of 100 mW/cm2 (AM1.5G), which can be attributed to the increased photocurrent generation in the third cell since the third cell has the complementary absorption with two bottom cells despite a slightly reduced Voc.

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