Vybrané kapitoly z biogeografie pre geografov

E-book

Mária Ganajová

The current teaching of chemistry has its specific problems. On one hand, due to the shift of the focus of chemistry curriculum towards theoretical content, the difficulty of chemistry material has increased, and in connection with this, students' interest in chemistry has decreased.

The lack of student interest in chemistry is mostly supported by the opinion that it is precisely chemistry that significantly contributes to the deterioration of environmental quality. On the other hand, we live in an era where we encounter chemical products practically everywhere. It is necessary to learn the basics of chemistry as well as possible, which makes the question of increasing interest in chemistry education and improving its effectiveness very relevant. State educational programs have been introduced into Slovak schools as a foundation for the creation of school educational programs. These emphasize not only acquiring a certain amount of knowledge but also the development and enhancement of key and specific competencies of students, preparing them for lifelong learning and their application in life.

Therefore, increasing attention is being paid to one of the fundamental didactic tools for raising student activity in teaching, and thus improving the effectiveness of chemistry education – learning tasks. From both theory and practice of chemistry teaching, we know that learning tasks, questions, examples, exercises, etc., are among the important components of every teaching lesson. Learning tasks are applied in all phases of teaching – in the motivational phase, the phase of acquiring knowledge, the phase of consolidating knowledge, and the phase of checking the acquired knowledge. It is therefore clear that every teacher will sooner or later find themselves in a situation where they will have to select learning tasks from textbooks, workbooks, collections of problems and examples, or create them themselves.

This scientific monograph is intended for educational specialists and chemistry teachers, aiming to familiarize them with examples of various types and forms of learning tasks and the basics of their creation in chemistry. It can also be helpful for them in preparing certification works focused on test creation and their statistical evaluation.

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E-book

Karel Saksl

Solving crystal structures is the royal discipline of X-ray crystallography. Its primary task, with the exception of defects, is to describe the atomic structure of the motif that, by its repetition, fills the volume of the entire crystal or crystalline phase. This task is nowadays more or less routine for single-crystal X-ray diffraction, which can locate hundreds to thousands of non-hydrogen atoms in large unit cells. However, in real practice, we often have material available only in powder form instead of single crystals. Solving the atomic structure from its X-ray diffraction data is non-trivial, mainly because the three-dimensional diffraction space of a single crystal is reduced to one dimension by measuring a large number of randomly oriented microcrystals (crystallites). Therefore, the solution itself requires, in addition to proper measurement methodology, the selection of suitable tools, procedures, and strategies that, through optimization, will lead to the solution and refinement of the given crystalline phase. The current limit of this method is approximately 100 non-hydrogen atoms in the asymmetric part of the unit cell, which, however, is sufficient for most inorganic materials.

The goal of these educational texts is to provide students in the second and third levels of university studies with specific guidance on solving crystal structures from powder X-ray diffraction data. These scripts build upon my first monograph and require practical knowledge of its content. Similar to my previous monograph, I offer solved examples without a deep theoretical introduction, demonstrating procedures and strategies leading to the correct solution of crystalline phases using the freely available GSAS-II program. The examples are arranged from simpler to more complex, and the reader will find many useful pieces of information in the literature references as well as in the comments below the line. Part of these scripts are data intended for your individual practice of the described procedures. 

Karel Sakls

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 Andrej Oriňak - Renáta Oriňaková - Andrea Fedorková

Nanotechnology represent the fastest developing science in the present. They are based on the technologies that enable the matter manipulation at atomic level. Nanotechnology offer prepartion of the new materials with unknown and very specific properties and functions.Recent nanotechnology still stay in formative phase of their development. But more and more they are visible with nano-specific phenomenons in the fundamental control of the properties as well mater behaviour. This is quite possible that without nanotechnology will not work any science to the future, moreover that science will not exist anymore. Nanotechnolgy will give a chance and force to transform world to more environmental and comfortable. Expected is expansion of the nanotechnolgy to molecular nanosystems – heterogenous nets, in which molecules and supramolecules work as the nanodevices. The computers and robots will be reduced to the small and ultrasmall dimensions. In medicine will foremost the application of nanotechnology in genetic therapy and elimination of ageing. Nanosurgery will work at molecular level, cancer cells will be identified early and filtered , then substituted with healthy and unchanged. It is necessary to inform university or high school students  about principles of nanotechnolgy, preparation of the nanostructures, functionality of them and to offer full representation about molecular systems and nanodevices; the methods of nanostructures characterization and about application in miniaturized systems. 

Authors

E-book

Monika Tvrdoňová - Miroslava Martinková

The scientific book of abstracts from conference „Novel Trends in Chemistry, Research and Education 2022“ is a summary of the contributions of conference participants, which contain the original results of their scientific and research activities. The contributions published in this volume can be divided according to content into the field of analytical, inorganic, organic, physical chemistry, biochemistry, didactics of chemistry and NMR spectroscopy.

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