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The coining technology produces a wide variety of commemorative coins with exquisite patterns. However, it often encounters defects such as insufficient filling, flash lines, light bands, and so on. Process engineers usually perform multiple tryouts to avoid the above-mentioned problems in actual production. This is not only time-consuming and laborious but also ineffective. The virtual tryout of the finite element method (FEM) could assist engineers to avoid the defects in the coining process with a great improvement in product quality. In order to exactly describe complex patterns of commemorative coins, a large number of elements are employed in the classical FEM. Even then, the three dimensional elements, which come in early contact with the reliefs of the punch/die, undergo large deformation and become distorted. Errors of contact judgment between the tools and the workpiece in the FEM occur during the simulation process. Taking into account the advantage of Non-Uniform Rational B-Spline (NURBS) basis functions when accurately describing complex boundaries or surfaces, isogeometric analysis (IGA) is developed for studying the material filling of coin cavities. Six numerical examples involving elastic and plastic analyses with/without contact issues are considered by the presented IGA frameworks and show good performance of the present method in simulating the cavity filling compared with ABAQUS. In addition, numerical findings also indicate that the proposed method exhibits excellent contact detection and strong anti-mesh distortion in large deformation of the coining process. These encouraging observations motivate us to explore the NURBS description of complicated reliefs of coins and the corresponding IGA framework for the coining process. [ABSTRACT FROM AUTHOR]

The article describes the life and work of Wilhelm Haarmann, a pioneer in the fragrance industry. Haarmann founded the company Haarmann & Reimer, which is now known as Symrise. His groundbreaking synthesis of vanillin was the starting point for the development of the fragrance and flavor industry. Haarmann was born in Holzminden in 1847 and studied chemistry in Göttingen and Berlin. He was a member of the German Chemical Society and participated in the Franco-Prussian War. In the letter, Haarmann describes his enthusiasm for the war and his participation in the military. He reports that he and his brother August joined a company and will soon begin drilling. The war takes him to the vicinity of Paris, where he has to endure until the spring of 1871. However, Haarmann's initial enthusiasm gives way to the realization that the war is one hardship after another. In terms of his chemical experiments, Haarmann was able to convert coniferin into coniferyl alcohol and isolate a new compound called coniferegenin. However, he could only determine the structure of this compound through chemical reactions, as instrumental analysis was not yet known at that time. The article describes the chemical investigations of Wilhelm Haarmann and Ferdinand Tiemann on the synthesis of vanillin from coniferin. Haarmann isolated coniferin from the cambial sap of coniferous trees and carried out various reactions to produce vanillin. Tiemann presented the results of the investigations at a meeting of the German Chemical Society and claimed that they had synthesized the odor and flavor component of vanilla. The research findings were confirmed by Pierre-Paulin Carles, who had already reported on the chemical composition of vanillin in 1872. In 1874, Wilhelm Haarmann founded the first company for the synthetic production of vanillin from coniferous wood in Holzminden. Together with his partner Tiemann, they succeeded in producing a fragrant substance from coniferin, which they identified as vanillin. Haarmann planned to sell the product to various industries such as the chocolate industry or bakeries. The vanilla plant, from which natural vanillin is obtained, originally grows in the rainforests of Mexico and was later cultivated in other tropical regions as well. The collaboration between Haarmann and Tiemann led to the development of a synthetic route for the production of vanillin from guaiacol. However, this process proved to be uneconomical and was not transferred to production. Instead, Tiemann succeeded in producing vanillin inexpensively from eugenol, which is contained in clove oil. This significantly reduced the price of synthetic vanillin. The artificial variant was now considered a financially interesting alternative to natural vanilla. The collaboration between the two was successful, although Reimer died of pulmonary tuberculosis in 1883. Haarmann was the entrepreneur and Tiemann the creative scientist who developed new products. Christian Andreas von Cothenius bequeathed one thousand gold talers in his will for the awarding of a golden commemorative coin for the best treatment of a prize question in the field of practical medicine. Gustav Robert Kirchhoff also received this award. There are reports of the collaboration between Georges de Laire and Charles Girard in the laboratory of Théophile-Jules Pelouze, where they synthesized fuchsin. Haarmann & Reimer were particularly interested in the production of synthetic vanillin, as it was more cost-effective than real vanilla. They commissioned Lina Morgenstern to create recipes using synthetic vanillin. [Extracted from the article]

The Czech National Bank issued nine commemorative coins in 2017. They included six silver CZK 200 coins issued to mark the 300th anniversary of the birth of Maria Theresa, 75th anniversary of operation called Anthropoid, 100th anniversary of the birth of Josef Kainar, 100th anniversary of the foundation of the "Sdružení českých umělců grafiků Hollar", the 650th anniversary of the chapel of Saint Wenceslas in the Saint Vitus Cathedral and 100th anniversary of the foundation of the Czech Astronomical Society. In addition, one silver CZK 500 coin was issued to mark the 100th anniversary of the battle of Zborov. The second two commemorative CZK 5,000 gold coins from the Castles cycle - dedicated to Bouzov and Pernštejn castles - were also issued. [ABSTRACT FROM AUTHOR]

The Czech National Bank issued nine commemorative coins in 2012. Five silver commemorative 200 CZK pieces have been produced. the 400th death anniversary of Rudolph II, the 150th foundation anniversary of the Sokol movement, the 100th foundation anniversary of the Junák movement, the 100th birth anniversary of Kamil Lhotdk and the 100th opening anniversary of the Municipal House in Prague. One silver 500 CZK issue celebrated the 100th birth anniversary of Jiří Trnka. Two gold 5,000 CZK pieces represented the Baroque bridge in Náméšt' nad Oslavou and the Negrelli viaduct in Prague. One gold 10,000 CZK issue celebrated the 800th anniversary of the Golden Bull of Sicily. [ABSTRACT FROM AUTHOR]