scholarly journals Two Design Principles for the Design of Demonstrations to Enhance Structure–Property Reasoning

2021 ◽  
Vol 11 (9) ◽  
pp. 504
Author(s):  
Marie-Jetta den Otter ◽  
Michiel Dam ◽  
Ludo Juurlink ◽  
Fred Janssen

Structure–property reasoning (SPR) is one of the most important aims of chemistry education but is seldom explicitly taught, and students find structure–property reasoning difficult. This study assessed two design principles for the development of structure–property reasoning in the context of demonstrations: (1) use of a POE task (predict–observe–explain) and (2) use of the domain-specific particle perspective, both to increase student engagement and to scaffold micro-level modeling. The aim of the demonstration series was to teach structure–property reasoning more explicitly to pre-university students (aged 15–16). Demonstrations pertained to the properties of metals, salts and molecular compounds. The SPR instrument was used as a pretest and posttest in order to gain insight into the effects on structure–property reasoning. In addition, one student (Sally) was followed closely to see how her structure–property reasoning evolved throughout the demonstrations. Results show that after the demonstrations students were more aware of the structure models at the micro-level. The students also knew and understood more chemical concepts needed for structure–property reasoning. Sally’s qualitative data additionally showed how she made interesting progress in modeling micro-level chemical structures. As we used conventional demonstrations as a starting point for design, this could well serve as a practical tool for teachers to redesign their existing demonstrations.

2018 ◽  
Vol 9 (5) ◽  
pp. 388-407
Author(s):  
Patricio Gigli ◽  
◽  
Donatela Orsi ◽  
Marisel Martín Aramburú ◽  
◽  
...  

This paper aims at describing the experience of the Cities for Entrepreneurs Program (Ciudades para Emprender or CPE) of the National Directorate of Community and Human Capital (which belongs to the SEPYME), National Ministry of Production. This paper starts from the premise that entrepreneurship takes place at the most micro level of the offer and, therefore, is a concept associated with the characteristics of the environment closest to that offer: the local territory. However, there is little history in the country of public policies relating the issue of entrepreneurship with the local management. That is why we take as a starting point the conceptualization of the chosen framework: local governments and the development issue, seen from the perspective of entrepreneurships. Moreover, an overview is given on the structural characteristics of municipalities in Argentina. In addition, some international experiences and attempts to promote entrepreneurship at a national level are analyzed. Finally, the Cities for Entrepreneurs Program (CPE) is outlined, based on a summary of the diagnoses of the Entrepreneurial Ecosystems of the selected cities and the tools used and their execution status at the time of publication of this paper.


2018 ◽  
Vol 21 (7) ◽  
pp. 533-542 ◽  
Author(s):  
Neda Ahmadinejad ◽  
Fatemeh Shafiei ◽  
Tahereh Momeni Isfahani

Aim and Objective: Quantitative Structure- Property Relationship (QSPR) has been widely developed to derive a correlation between chemical structures of molecules to their known properties. In this study, QSPR models have been developed for modeling and predicting thermodynamic properties of 76 camptothecin derivatives using molecular descriptors. Materials and Methods: Thermodynamic properties of camptothecin such as the thermal energy, entropy and heat capacity were calculated at Hartree–Fock level of theory and 3-21G basis sets by Gaussian 09. Results: The appropriate descriptors for the studied properties are computed and optimized by the genetic algorithms (GA) and multiple linear regressions (MLR) method among the descriptors derived from the Dragon software. Leave-One-Out Cross-Validation (LOOCV) is used to evaluate predictive models by partitioning the total sample into training and test sets. Conclusion: The predictive ability of the models was found to be satisfactory and could be used for predicting thermodynamic properties of camptothecin derivatives.


2020 ◽  
pp. 1-20 ◽  
Author(s):  
Friederike Enßle ◽  
Ilse Helbrecht

Abstract This article aims to enhance the conceptual debate on diversity in old age by exploring the interplay of diversity in later life and images of old age. We argue that the analysis of images of old age on the micro-level is a fruitful methodology in order to unravel the meaning of diversity in later life. Drawing on findings from qualitative research in Berlin, we explore how new and diverse imaginations, experiences and lifestyles of old age emerge. The conceptual focus on images of old age enables us to investigate further what diversity in later life comprises and how it simultaneously fosters the genesis of new images of old age. The manifold new images we found in our research suggest that prevalent societal discourses about old age on the macro-level are rather deceptive and represent mostly stereotypes such as ‘active agers’ or ‘frail and dependent elders’. We offer three explanations why alternative images of old age are currently barely present in public discourse: (a) the actors transmitting images of age; (b) the institutionalisation of the images; and (c) the challenge to communicate complexity. We conclude by suggesting that images of old age are a promising starting point to explore and make visible both the diversity of social groups within the older generation as well as the heterogeneity of older individuals.


2013 ◽  
Vol 86 (3) ◽  
pp. 401-422 ◽  
Author(s):  
Kshitij C. Jha ◽  
Mesfin Tsige

ABSTRACT Elastomers have varied applications from adhesives, sealants, encapsulants, and coatings to specialty usage in electronics, aviation, optical, and communications industries due to their high structural stability. In addition, more and more biological applications of elastomeric compounds are gaining ground, particularly in mimetic architecture. Modeling and simulation provide tools by which the interactions leading to various structure–property relationships can be explored at the micro level. An understanding of these processes could cut down on the extensive and expensive trial-and-error experiments as well as provide a benchmark for material design. This review article explores the work done by different groups, especially at the molecular level, to model the properties of both thermoplastic and thermoset elastomers. Each presents its own challenges and solutions: from microphase separation to network building and force field parameterization. The results of these modeling efforts along with the challenges are presented in this review work.


1996 ◽  
Vol 443 ◽  
Author(s):  
Neil H. Hendricks

AbstractFor over two years, intensive efforts at SEMATECH and elsewhere have focused on identifying low dielectric constant (low ε) materials which possess all of the required properties and processing characteristics needed for integration into standard IC fabrication lines. To date, no material candidate has been shown to satisfy this impressive list of requirements. For some candidates, drawbacks related to material properties such as poor thermal stability or electrical performance have been identified; in other cases, problems in process integration, for example difficulties in patterning have stalled progress.In this paper, most of the current leading candidates for the low ε IC IMC application are identified and discussed. An attempt is made to correlate structure/property relationships in these materials with their relative attributes and deficiencies as they relate to the IMD application. Key differences in chemistry and property/processing characteristics are contrasted for low c silicon-oxygen polymers and for purely organic polymers. Novel dielectrics such as porous organic and inorganic thin films are also discussed in terms of their properties and associated process integration challenges. Since the needs for global planarization and low c IMD are occurring within roughly the same generation of minimum feature size (˜ 0.25 μm), the chemical mechanical polishing (CMP) of low dielectric constant thin films and/or of SiO2 layers deposited above them is briefly discussed. Both subtractive metalization and damascene processes are included, and the required low dielectric constant film properties and processing characteristics are contrasted for each process. Finally, the author's views on future trends in low dielectric constant materials development are presented, with an emphasis on identifying the types of chemical structures which may prove viable for this most demanding of all polymer film applications.


2020 ◽  
Vol 245 ◽  
pp. 04044
Author(s):  
Jérôme Fulachier ◽  
Jérôme Odier ◽  
Fabian Lambert

This document describes the design principles of the Metadata Querying Language (MQL) implemented in ATLAS Metadata Interface (AMI), a metadata-oriented domain-specific language allowing to query databases without knowing the relation between tables. With this simplified yet generic grammar, MQL permits writing complex queries more simply than with Structured Query Language (SQL).


2021 ◽  
Vol 12 (1) ◽  
pp. 273-290
Author(s):  
Michael Nguyen ◽  
Yuqing Qiu ◽  
Suriyanarayanan Vaikuntanathan

Studies of biological systems and materials, together with recent experimental and theoretical advances in colloidal and nanoscale materials, have shown how nonequilibrium forcing can be used to modulate organization in many novel ways. In this review, we focus on how an accounting of energy dissipation, using the tools of stochastic thermodynamics, can constrain and provide intuition for the correlations and configurations that emerge in a nonequilibrium process. We anticipate that the frameworks reviewed here can provide a starting point to address some of the unique phenomenology seen in biophysical systems and potentially replicate them in synthetic materials.


Author(s):  
Sebastian Günther

Internal DSLs are a special kind of DSLs that use an existing programming language as their host. To build them successfully, knowledge regarding how to modify the host language is essential. In this chapter, the author contributes six DSL design principles and 21 DSL design patterns. DSL Design principles provide guidelines that identify specific design goals to shape the syntax and semantic of a DSL. DSL design patterns express proven knowledge about recurring DSL design challenges, their solution, and their connection to each other – forming a rich vocabulary that developers can use to explain a DSL design and share their knowledge. The chapter presents design patterns grouped into foundation patterns (which provide the skeleton of the DSL consisting of objects and methods), notation patterns (which address syntactic variations of host language expressions), and abstraction patterns (which provide the domain-specific abstractions as extensions or even modifications of the host language semantics).


Author(s):  
Kristóf Csorba ◽  
Ádám Budai ◽  
Judit Zöldföldi ◽  
Balázs Székely

GrainAutLine is an interdisciplinary microscopy image analysis tool with domain specific smart functions to partially automate the processing of marble thin section images. It allows the user to create a clean grain boundary image which is a starting point of several archaeometric and geologic analyses. The semi-automatic tools minimize the need for carefully drawing the grain boundaries manually, even in cases where twin crystals prohibit the use of classic edge detection based boundary detection. Due to the semi-automatic approach, the user has full control over the process and can modify the automatic results before finalizing a specific step. This approach guarantees high quality results both in cases where the process is easy to automate, and also if it needs more help from the user. This paper presents the basic operation of the system and details about the provided tools as a case study for an interdisciplinary, semi-automatic image processing application.


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