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PL
Realizowane w Zakładzie Chemii Organicznej badania pozostają w nurcie aktualnych wyzwań współczesnej chemii organicznej a nowoczesne, wielopłaszczyznowe podejście do badań naukowych pozwala na formułowanie przełomowych wniosków odnośnie mechanizmów reakcji chemicznych, ważnych z preparatywnego punktu widzenia.
EN
This article presents the results of analysis of Czech and Russian textbooks intended for organic chemistry teaching at upper secondary schools. In principle, the estimation of textbook didactic capacity is based on decomposition of the textbook content into a set of different objects and their subsequent frequency analysis. In this study, three Czech textbooks and three Russian textbooks were characterized by particular and total didactic capacity coefficients. The indifference of the calculated didactic capacities was tested by chi-square statistics at a level of significance α = 0.05. The results show that the selected Czech and Russian textbooks are not significantly different.
EN
John Read and James Partington were both prominent and highly respected academics, chemists, authors and teachers during the middle decades of the 20th century. Their books were widely read throughout this period and played a major role in educating and raising the awareness of chemistry among young people and adults. Today their names are forgotten. The aim of the present article is to re-establish these two remarkable men and to bring them to the forefront of educational programs. An outline is given of their careers as chemists, set against the background of the times they lived in, giving an emphasis to their formidable literary output. Although they had widely contrasting personalities, and were specialists in three different fields of chemistry, Read: organic, Partington: physical and inorganic, they both recognized the great importance of setting chemistry in an historical context. Accordingly, they both wrote many works on the origins and development of chemistry and included much historical material in their textbooks. This added not only a great interest to the subject, but also set it in a broader cultural context, which is so clearly lacking in today’s chemistry teaching programs. A chronological list of their books is given and short contrasting fragments from four of them are analysed. Not only are these books of great interest, but they serve as an outstanding foundation for teaching the principles of chemistry today. A recommendation is made to incorporate one work of each author as compulsory reading material for students today, and in future years.
PL
W połowie dwudziestego wieku John Read i James Partington byli wysoko cenionymi naukowcami w dziedzinie chemii, autorami i nauczycielami. Ich książki były czytane w szerokich kręgach i odgrywały ważną rolę w edukacji i w rozszerzaniu świadomości chemii wśród młodzieży i dorosłych. Niestety, dzisiaj ich nazwiska są zapomniane. Celem tego artykułu jest przywrócenie należytego miejsca w historii nauki tym dwóm niezwykłym postaciom i wprowadzenie ich na pierwszy plan we współczesnych programach edukacyjnych. Ich życiorysy zostały przedstawione w skrócie na tle epoki, w której żyli. Szczególny nacisk położono na ich olbrzymi wkład w literaturę. Read i Partington posiadali zupełnie odmienne osobowości i specjalizowali się w trzech dziedzinach chemii, a mianowicie Read: w organicznej, Partington: w fizycznej i nieorganicznej. Mimo tych różnic, obaj chemicy w pełni doceniali konieczność przedstawiania chemii w perspektywie historycznej. W związku z powyższym autorzy ci napisali wiele prac na temat początków chemii i rozwoju nauk chemicznych, a także uwzględniali materiały historyczne w podręcznikach. Materiały te w dużym stopniu wzbogacały i uprzyjemniały nauczanie chemii. Równocześnie uświadamiały czytelnikowi, jak doniosłą rolę odegrała chemia w dziejach ludzkości. Takiego uświadamiania w jaskrawy sposób brakuje w dzisiejszych programach nauczania chemii. Ponadto przedstawiono w układzie chronologicznym listę ich książek i dokonano szczegółowej analizy czterech różnych fragmentów z tych dzieł. Książki Johna Reada i Jamesa R. Partingtona są nie tylko bardzo interesujące, ale również stanowią doskonały fundament do nauczania chemii obecnie. Przedstawiono propozycję, żeby chociaż jedna książka tych autorów stała się obowiązującą lekturą dla studentów chemii, zarówno dzisiaj, jak i w przyszłości.
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Content available remote Nowe realizacje procesu Meyera
PL
Najbardziej uniwersalną metodą syntezy alifatycznych nitrozwiązków jest nukleofilowe podstawienie z udziałem anionów azotanowych(III), zwane reakcją Meyera. Dokonano przeglądu i dyskusji nowych realizacji tego procesu. Wiele odkrytych w ostatnim czasie reakcji tego typu przebiega zgodnie z regułami zielonej chemii i w stosunkowo łagodnych warunkach.
EN
A review, with 28 refs., of processes for prepn. of aliph. nitrocomps. by nucleophilic substitution involving the nitrite anion. Several reactions carried out via green protocol under mild conditions were included.
EN
Understanding of the fundamental law and mechanisms governing the phenomenon of life is an inherent feature of human civilization. With the birth of philosophy comes first speculation about the physical conditions of life processes, which consequently will lead to the formation of the first scientific theories. Among them an important role plays the Hippocratic humoral theory. This scientific rout will be taken by the next generations of researchers seeking for the most appropriate methods and precise language of science. A significant breakthrough came in the 16th century, when Paracelsus coined his philosophical and alchemical doctrine which gives such attention to perpetual changes in living organisms, then described on the basis of transmutation. Nearly three centuries later, in the early nineteenth century the polish physician and chemist Jędrzej Śniadecki introduced the concept of metabolism, based on the principles that are present in compounds and chemical reactions. Just a dozen years later, in 1828, Wöhler`s synthesis of urea gives birth to organic chemistry. Language of chemistry has become a tool for the description of biological phenomena, slowly building up physiological chemistry which shortly was turned to biochemistry. For a young science one of the first challenges was the level of the rudimental for the living organisms dyes, which rightly appeared as essential for the understanding of the chemical nature of the phenomena of life. From that point the studies on chlorophyll (Pelletier, Caventou, Shunck, Hoppe- -Seyler) and hemoglobin (Hünefeld, Funke, Hoppe-Seyler) become crucial topic. In this pioneering studies significant, and sometimes decisive role was to be played by Polish scientists (Teichmann, Marchlewski, Nencki, Zaleski). Especially a few years’ time and very intense cooperation of Leon Marchlewski and Marcel Nencki would bring momentous decision. Marchlewski’s bold hypothesis about the chemical unity on the level of the basic dyes in plant and animal worlds was fully confirmed in the experimental procedure and the results achieved by Nencki brought the solution to the problem of the chemical structure of hemin. Joint research of Polish scientists became the foundation of modern biochemistry and had changed the biological and medical sciences so deeply, that we can talk about “biochemical revolution”. The following paper is an evaluation of the speech held by me during X National Organic Chemistry Symposium – OSCO X, Lodz, April 16–18, 2015.
PL
W bieżącym roku minęło 50 lat od dnia śmierci Wiktora Aleksandra Lampego, wybitnego chemika specjalizującego się w syntezie i analizie organicznej, bardzo uzdolnionego ucznia prof. Stanisława Konstaneckiego z Uniwersyetu w Bremie. Wiktor Lampe należał do pokolenia organizatorów studiów chemicznych w odrodzonym Uniwersytecie Warszawskim, był też jednym z członków-założycieli Polskiego Towarzystwa Chemicznego. Nie do przecenienie są jego zasługi w doprowadzeniu do wybudowania nowoczesnego gmachu chemii i usilnych zabiegów o jego odbudowę ze zniszczeń wojennych.
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Content available remote Okruchy IX. Maciej
10
EN
Commonly available hydrolytic enyzymes are capuble of recognizing heteroatom stereogenic centres. A review of the application of these enzymes in the preparation of optically active sulfur and phosphorus compounds, based on the results from the authors' Laboratory, is presented.
PL
Powszechnie dostępne enzymy hydrolityczne są w stanie rozpoznać stereogenne centra heteroatmowe. Niniejszy przegląd przedstawia zastosowanie tego typu enzymów w syntezie optycznie czynnych połączeń siarki i fosforu ze szczególnym uwzględnieniem wyników badań pochodzących z Laboratorium autorów.
EN
Professor Maciej Wiewiórowski is one of the most distinguished organic chemists in the world. He got his PhD in 1950 working on the chemical transformations of codeine with Professor J. Suszko at Poznań University. Next, he started developing his own research programme concerning the alkaloid composition of certain Lupinus species. Several of his students then are still continuing the structural and synthetic research in this topic. At the end of the fifties, he spent quite some time on his first long-term post-doctoral fellowship working with Professor Leo Marion in the laboratory of the National Research Council of Canada in Ottawa, and it appeared to be the beginning of his fruitful collaborations with many outstanding scientists in the world in the subsequent years. When working in this foreign laboratory, he took the opportunity to become acquainted with many modern research techniques, especially column chromatography and IR as well as other spectroscopic methods, which enabled him to propagate and popularize these techniques in our country when he returned. In the late sixties, being the Head of the Stereochemistry and Organic Spectrochemistry Division at the Adam Mickiewicz University in Poznań, he began to organize, under the auspices of the Polish Academy of Science, a new field of research in Poland, then undeveloped worldwide, concerning the synthesis of nucleic acids. He both gathered young scientists, giving them special training, and organized new laboratories outside the University. In the early seventies, he moved with his group to the tentative laboratories at Noskowskiego Street in Poznań, there systematically and intensively expanding this research center, which finally resulted in the creation of the Institute of Bioorganic Chemistry of the PASc, a leader in the scientific world in carrying out modern biochemical research in nucleic acid as well as in protein chemistry. During recent years, already being retired, he is still very active in the life of the Institute , including carrying out research mainly on the reaction of nucleosides in a solid state.
12
Content available remote Aromatyczność - podstawowe pojęcia współczesnej chemii organicznej
EN
Aromaticity is one of the most often used terms in chemistry. It is not a single property, but a multidimensional phenomenon which can be defined only by convention. Various typical characteristics of aromaticity not always occur to be equivalent. As a ground for these definitions it is usually accepted that aromatic compounds are those cyclic p-electron systems which exhibit the following properties: (i) They are more stable than the non-cyclic analogues; (ii) Their bond lengths are intermediate between the typical double and single bonds; (iii) They exhibit special magnetic properties: in the external field the p-electron ring current is induced. Sometimes an additional criterion is postulated: the aromatic systems react in the way to retain their p-electron structure. Most often it means that the substitution is preffered over the addition reaction. While the first three criteria may be transformed into quantitative parameters called aromaticity indices, reactivity can be used only in a qualitative way.
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