50 Years Liquid Crystal Research-A Personal Retrospective

References

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• The mixtures were designated with numbers according to their sequence of elaboration, abbreviated Mi 1, Mi 2 etc. Some years ago in the publication Shi , J. , Wang , C. , Surendranath , V. , Kang , K. , & Gleeson , J. T. ( 2002 ). Liq. Cryst. , 29 , 877 , a mixture with the same composition and the same designation as our Mi 5 was the main topic of detailed physical investigations, without referring to any of our papers. Has the mixture been reinvented?
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• This development can be seen by checking the database LiqCryst [28] .
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• A report about this matter, prepared by the historian Schrödter, E., can be found in the book Beiträge zur Geschichte der Martin-Luther-Universität 1502–2002, ed. by H.-J. Rupieper, Mitteldeutscher Verlag: Halle 2002, pp. 658–660. This report shows that Demus's connections with the Stasi have not been devoted to spying on colleagues or destroying careers of them, as in Germany automatically is alleged, but it shows that it is related to the research on liquid crystals. On p. 658 of his article Schrödter states: ‘The preserved reports … prove the efforts to improve the difficult boundary conditions for the research. This mainly concerns scientific relations to Western partners and the latent shortage of technical equipments and chemical basic materials.’ This report of a historian is a seldom case. At present by a respective law persons concerned are not permitted to see the documents related to their own case. Therefore it is difficult to perform legal proceedings in order to clarify eventual accusations. By the side, the good working atmosphere in the Institute of Physical Chemistry Halle was famous, not at least due to the professors who guarded the institute against unpleasant political influences in the frame of their facilities .
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• Hecht , A. Die Wissenschaftselite Ostdeutschlands. Feindliche Übernahme oder Integration?, Faber & Faber: Leipzig 2002, a) academic teachers except medical faculty see p. 52, b) the average of all dismissed academic teachers was 72%, see p. 59. Dismissals of academic teachers in Germany already had a sad tradition: in 1933–1936 by the National-Socialists in average 14.3% were dismissed [33]. According to Michael Grüttner (Spiegel Online Unispiegel 9. August 2010) after 1945 about 50% of the academic personnel was dismissed by the Allies, but most of them returned to their academic positions in the next years in the Western zones of Germany. In the Soviet zone the number of dismissals was higher; many of the dismissed persons went to Western Germany .
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• The well known German historian Arnulf Baring, who still is frequently invited for public discussions in the leading German TV stations, in his book Deutschland, was nun? Siedler Verlag: Berlin 1991 p. 59 characterized the situation in East Germany as follows: ‘The regime has nearly half a century the people made dwarfish, and their bringing up and education ruined …. if people now call themselves jurist or economist, educationalist, psychologist, sociologist, even physician or engineer, it does not matter: His knowledge is largely totally useless’. In this climate it was difficult to be acknowledged, despite positive judgement [35] .
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• The German Patent Office in an international study (http://www.paton.tu-ilmenau.de/pdf/vorlesung/lb4_analyse_beispiel.pdf) searched for the ‘Leading Technician’, a title which was granted according to the number of citations of scientific papers and patents. In the field of liquid crystals Dietrich Demus in 1994 and 1998 was identified as leading technician (Fig. 9) .
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• In 1991 in Halle I have been formally registered as jobless person in ‘Early Retirement’ (Vorruhestand). Most of the people in this situation did not find an employment again .
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• This paper has not been published before and it has not been sent simultaneously for publication elsewhere.
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