Simple methods for determining the enantiomeric purity of mevalonolactone and linalool by NMR using the chiral shift reagent Eu(hfc)3 are reported. These methods are more reliable than polarimetry and require only a few milligrams of sample to detect as little as 2% of the minor enantiomer. The accuracy of these methods is limited primarily by spectral resolution for samples of high enantiomeri...

We use Clebsch potentials and an action principle to derive a complete closed system of gauge-invariant equations for sound superposed on a general background flow. Our system reduces to the Unruh [Phys. Rev. Lett. 46 (1981) 1351] and Pierce [J. Acoust. Soc. Am. 87 (1990) 2292] wave equations when the flow is irrotational, or slowly varying. We illustrate our formalism by applying it to waves p...

We study the general L0-regular gl(2) spin chain, i.e. a chain where the sites {i, i + L0, i + 2L0, . . . } carry the same arbitrary representation (spin) of gl(2). The basic example of such chain is obtained for L0 = 2, where we recover the alternating spin chain. Firstly, we review different known results about their integrability and their spectrum. Secondly, we give an interpretation in ter...

The authors are listed out of order. Please view the correct author order and affiliations here: Wanshuai Li, YongWang, Qi Zhang, Lili Tang, Xiaoping Liu, Yunhua Dai, Liang Xiao, Shuguang Huang, Lu Chen, Zhongmin Guo, Jim Lu, Kai Yuan 1 The Department of Cardiothoracic Surgery, No. 2 People's Hospital of Changzhou, 29 Xinglong Xiang, Changzhou, Jiangsu, 213004, China, 2 Changzhou GoPath Diagnos...

Human kind has entered a brand new relationship with the earth. The constant and increasing pressures were exerting threaten our planets ability to sustain life itself. In the last decade the problems of atmospheric change have been gravely advanced by pollution resulting from human activities. Human being are responsible for releasing huge quantity of pollutants in the environment the majority...

Bibliographie: Mühe, Marieluise: Damm, Juliana & Mlynek, Maren (2021). Die AfD und die Geflüchteten. Was rechte Ideologie gesellschaftlich bewirkt. (Interdisziplinäre Schriftenreihe des Centrums für Interkulturelle Europäische Studien Vol. 19), Stuttgart: ibidem-Verlag. 251 Seiten, ISBN: 978-3-8382-1351-4, 29,90 Euro, ZRex – Zeitschrift Rechtsextremismusforschung, 2-2021, S. 349-350. https:...

In this paper, we consider the diffusive Nicholson's blowflies model in spatially heterogeneous environment when diffusion rate is large. We show that ratio of average maximum per capita egg production to death affects dynamics model. The unique positive steady state locally asymptotically stable if less than a critical value. However, greater value, large time delay can make unstable through H...