EXPERIMENTS
Coating Metals With Zinc and Method for Measuring the Thickness of the Layer
Miroslav Minchev
Geo Milev School of Mathematics and Natural Science – Stara Zagora (Bulgaria)
https://doi.org/10.53656/nat2021-5.01
Abstract. When a copper coin is immersed with zinc into a solution of a zinc salt (, etc.) an electrochemical reaction occurs in the mixture. As a result, a thin layer of zinc appears on the surface of the copper which gives the impression for silver color…
FROM THE RESEARCH LABORATORIES
Potential Applications оf Antibacterial Compounds in Edible Coating as Fish Preservative
Maulidan Firdaus, Desy Nila Rahmana, Diah Fitri Carolina,
Nisrina Rahma Firdausi, Zulfaa Afiifah,
Berlian Ayu Rismawati Sugiarto
Sebelas Maret University – Surakarta (Indonesia)
https://doi.org/10.53656/nat2021-5.02
Abstract. Fish is a product that breaks down quickly due to biochemical reactions that cause a decrease in the quality of its nutritional and sensory values. Natural preservatives make fish safer for consumption than fish preserved with formalin…
CURRICULUM MATTERS
Molecular Model аnd its Simplification in Teaching Stereoisomerism at Undergraduate Level
Girija Shankar Singh
University of Botswana – Gaborone (Botswana)
https://doi.org/10.53656/nat2021-5.03
Abstract. The role of molecular models in teaching chemistry is well-known. It is widely used in explaining the shape of molecules. Several authors have reported the difficulty in teaching stereochemistry/chirality…
NEW APPROACHES
Meteors. Basic Concepts And Terminology
Valentin Velkov
Astronomical club “Canopus” - Varna
https://doi.org/10.53656/nat2021-5.04
Absract. This article discusses some basic concepts related to meteor astronomy, as well as the use of the correct terminology when working in Bulgarian...
From The Formation Of The Earth To The Establishment Of Luka
Assoc. Prof. Zdravka Kostova, DSc.
Sofia University
https://doi.org/10.53656/nat2021-5.05
Absract. The article discusses successive stages in the evolution of life up to the establishment of the prokaryotic cell emphasizing the transitions from pre-biotic environment to organic precursors, pre-RNA-RNA, RNA-proteins-DNA, DNA-LUCA...
HISTORY & PHILOSOPHY OF SCIENCE
1300 Years Since The Birth Of Geber – Beginning And Foundation Of Arabic Alchemy
Nano Stepanov, chemical engineer
https://doi.org/10.53656/nat2021-5.06
Absract. Geber (Latinized name of Jabir ibn Hayyan (c. 721 – c. 815)) is among the most notable representatives of medieval chemistry...