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Based on four extant letters the famous Polish alchemist Michael Sendivogius wrote to Emperor Rudolf II and his first chamberlain Hans Popp between 1597 and 1602, this paper adds to a growing body of revisionist scholarship on alchemy in Rudolfine Prague. Unlike most of his many rivals – including luminaries such as John Dee and Michael Maier – who hoped for the Emperor's patronage in vain, Sendivogius officially became a courtier at the imperial court in 1594. As such he was in the privileged position of having access to the Emperor and his close advisors. The surviving correspondence shows how the Pole successfully balanced his alchemical promises against Rudolf's expectations for a number of years. The fact that even Sendivogius found it difficult to translate imperial patronage into ready money suggests that Emperor Rudolf II was considerably more circumspect and less gullible than the widespread cliché suggests. Fully contextualised by all available sources on Sendivogius' early career, the four letters emerge as important documents regarding the Polish adept and alchemical patronage in Rudolfine Prague. They also shed new light on the circumstances which led to the writing and publication of Sendivogius' famous treatise De lapide philosophorum (Novum lumen chymicum). 相似文献
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Paula Garcia-Oliveira Anxo Carreira-Casais Eliana Pereira Maria Inês Dias Carla Pereira Ricardo C. Calhelha Dejan Stojkovi Marina Sokovic Jesus Simal-Gandara Miguel A. Prieto Cristina Caleja Lillian Barros 《Molecules (Basel, Switzerland)》2022,27(19)
Several scientific studies have been proving the bioactive effects of many aromatic and medicinal plants associated with the presence of a high number of bioactive compounds, namely phenolic compounds. The antioxidant, anti-inflammatory, and antimicrobial capacities of these molecules have aroused high interest in some industrial sectors, including food, pharmaceuticals, and cosmetics. This work aimed to determine the phenolic profiles of the infusions and hydroethanolic extracts of five plants (Carpobrotus edulis, Genista tridentata, Verbascum sinuatum, Cytisus multiflorus, and Calluna vulgaris) that have been employed in many traditional preparations. In addition, the antioxidant, antimicrobial, anti-inflammatory, and anti-tumoral activity of each different preparation was evaluated using in vitro assays. The HPLC-DAD-ESI/MS profile revealed the presence of eighty phenolic compounds, belonging to seven different families of compounds. Regarding antioxidant properties, the hydroethanolic extract of C. edulis showed a potent effect in the TBARS assay (IC50 = 1.20 µg/mL), while G. tridentata hydroethanolic extract achieved better results in the OxHLIA test (IC50 = 76 µg/mL). For cytotoxic and anti-inflammatory results, V. sinuatum infusions stood out significantly, with GI50 = 59.1–92.1 µg/mL and IC50 = 121.1 µg/mL, respectively. Finally, C. edulis hydroethanolic extract displayed the most relevant antibacterial activity, showing MBC values of 0.25–1 mg/mL, while G. tridentata hydroethanolic extract exerted the greatest antifungal effects (MFC of 0.5–1 mg/mL). The results of this study deepen the knowledge of the phenolic profiles and also provide evidence on the bioactive properties of the species selected, which could be considered highly valuable options for research and application in several sectors, namely food, cosmetics, and pharmaceuticals. 相似文献
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《Ambix》2013,60(3):202-225
AbstractThis article explores the strategies of and the reasons behind the reworking of pseudo-Albertus Magnus's Semita recta into the Mirror of Lights. I argue that the redactor sought to provide a more comprehensive defence of the legitimacy of alchemy than found in the Semita recta. In the process of doing so, he reshaped the original text so as to present three units that addressed different parts of the alchemical opus: first, theory and justification of alchemy; second, basic information on substances and procedures; and, third, practice. The redactor employed sophisticated textual tools identical to those seen in scholastic texts. These strategies, I argue, constitute part of the redactor's attempt to bring authority and credibility to his project and to alchemy in general. Certainly, much more attention needs to be paid to these experiments of textual alchemy in order to understand the practice of alchemy in the late medieval period. 相似文献
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Electrical polarizability tensors and dipole noments for closed-shell molecules are calculated using a self-consistent field perturbation theory in which each molecular orbital is written as a linear combination of electric-field-dependent atomic functions Values calculated using different sets of atomic functions are compared with experiment and with previous theoretical work. 相似文献
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The Haber mechanism describing the process of hydrogenating nitrobenzene to aniline is shown to be incorrect and a new mechanism is proposed. 相似文献
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S.Fazal Hussain M.Tariq Siddiqui G. ManiKumar Maurice Shamma 《Tetrahedron letters》1980,21(8):723-726
Proaporphines undergo light catalyzed rearrangement. Pakistanamine () is thus converted into lumipakistanine (), while pronuciferine () and N-acetylnorpronuciferine () afford the corresponding C-9 hydroxylated aporphines and . Possible biogenetic schemes for the formation of C-8, C-9-, and C-8,9-substituted aporphines are presented. 相似文献
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Ettore Perrone Marco Alpegiani Angelo Bedeschi Franco Giudici Giovanni Franceschi 《Tetrahedron letters》1984,25(22):2399-2402
Preparation and reactivity of novel azetidinyl(phosphoranylidene)acetates implicated in penem synthesis is discussed 相似文献
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