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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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Viral infections pose a persistent threat to human health. The relentless epidemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global health problem, with millions of infections and fatalities so far. Traditional approaches such as random screening and optimization of lead compounds by organic synthesis have become extremely resource- and time-consuming. Various modern innovative methods or integrated paradigms are now being applied to drug discovery for significant resistance in order to simplify the drug process. This review provides an overview of newly emerging antiviral strategies, including proteolysis targeting chimera (PROTAC), ribonuclease targeting chimera (RIBOTAC), targeted covalent inhibitors, topology-matching design and antiviral drug delivery system. This article is dedicated to Prof. Dr. Erik De Clercq, an internationally renowned expert in the antiviral drug research field, on the occasion of his 80th anniversary.  相似文献   

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Hilde Norrgrén 《Ambix》2020,67(2):153-173
The article explores the practical and social circumstances of the alchemical experiments performed by the Norwegian priest and missionary Hans Egede (1686–1758) in the Colony of Hope in Greenland. Sources not previously used in connection with Egede’s alchemy are used to investigate in which ways his situation in the colony affected alchemical practice. A lack of fuel is found to have been a main obstacle which may have limited the number of experiments that Egede was able to perform in Greenland. At the same time, the area had natural resources that were useful to the alchemist, and Egede’s position as head of the colony gave access to resources that facilitated alchemical practice.  相似文献   

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Thermodynamic integration is a widely used method to calculate and analyze the effect of a chemical modification on the free energy of a chemical or biochemical process, for example, the impact of an amino acid substitution on protein association. Numerical fluctuations can introduce large uncertainties, limiting the domain of application of the method. The parametric energy function describing the chemical modification in the thermodynamic integration, the "Alchemical path," determines the amplitudes of the fluctuations. In the present work, I propose a measure of the fluctuations in the thermodynamic integration and an approach to search for a parametric energy path minimizing that measure. The optimal path derived with this approach is very close to the theoretical minimum of the measure, but produces nonergodic sampling. Nevertheless, this path is used to guide the design of a practical and efficient path producing correct sampling. The convergence with this practical path is evaluated on test cases, and compares favorably with that of other methods such as power or polynomial path, soft-core van der Waals, and some other approaches presented in the literature.  相似文献   

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Jane Marcet's Conversations on Chemistry (first edition, 1806) was possibly the best-selling English-language chemistry book of the first half of the nineteenth century. Recent scholarship has explored the degree to which her husband assisted in the writing of the book, without diminishing the high merits of the author. Previously unpublished correspondence, some of which appears here for the first time, casts new light on the social and professional circle of Jane and Alexander Marcet, including its influence on Jane's book. One of the members of that circle was a hitherto unrecognised but highly capable young female chemist, Frederica Sebright. The story told here underlines the tensions in elite circles in early nineteenth-century England between broad-minded acceptance and patronising limitations for women in science.  相似文献   

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Protein patterns of nasal lavage fluid (NLF) and bronchoalveolar lavage fluid (BALF) were analyzed with two-dimensional gel electrophoresis (2-DE) and a number of previously unidentified proteins (lipocalin-1, cystatin S, transthyretin, immunoglobulin binding factor and an 11 kDa fragment of albumin) were identified by N-terminal amino acid sequencing. Lipocalin-1 was shown to be a dominant protein in NLF from healthy subjects but was almost undetectable in NLF from a patient with asthma. It further appeared that lipocalin-1 in NLF consists of eight forms with pIs between 5.2 and 5.5: three with the expected Mr of 17500, two with increased Mr (18000), and three truncated variants with Mr of 17000. Two forms of cystatin S were identified both in NLF and BALF: one with pI 5.1 and Mr 13000, and the other with pI4.9 and Mr 13500. The distribution of the two forms was clearly different in NLF and BALF from healthy subjects with the 4.9/13500 form constituting only about 13% in NLF but 69% in BALF. In NLF from subjects with upper airway irritation a twofold increased proportion of the 4.9/13500 form was detected. Amino acid sequence data and the spot position indicate that the 4.9/13500 form might be a phosphorylated variant of cystatin S. Lower levels of both forms of cystatin S were found in BALF from smokers than nonsmokers. The levels of transthyretin in NLF were decreased in subjects exposed to irritating chemicals. Finally, higher levels of IgBF were found in BALF from smokers than nonsmokers. Taken together, these results illustrate the potential biomedical and clinical applications of identifying proteins in 2-DE patterns of human BALF and NLF. The possibility to describe and monitor airway disorders at the molecular level is inferred.  相似文献   

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Mauveine, a chemical icon, is no longer commercially available. If nowadays one wanted to have a sample of the original Perkin, or Caro, mauveine, and see its colour, where would one find it? The answer is on UK Victorian 6d postage stamps from 1867–1880. This was found from a comparison with historical samples of mauveine, from both William Perkin and a Heinrich Caro sample (here analysed for the first time). These have distinctly different compositions and this was used to identify the origin of mauveine in the postage stamps, with evidence found for mauveine made by both Perkin’s and Caro’s synthesis.  相似文献   

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李井奎 《高分子学报》2018,50(12):41-51
长期以来,国内外学术界对于凯恩斯与哈耶克的理论对手形象根深蒂固。然而,近几十年的经济思想史研究告诉我们,这一理论对手的形象反映出来的是我们对凯恩斯与哈耶克关于货币、资本和商业周期论述的误读有多深。本文通过对1930年代发生在两者之间的著名争论详加探究,综合近年来的经济思想史研究成果发现:至少在维克赛尔的分析传统之下,凯恩斯与哈耶克远不是彼此对立的敌手,而是并肩作战的同袍;现代宏观经济学的发展之所以偏离了两者当年研究的方向,乃是经济学界职业发展的内在逻辑而非经济学议题的重要性使然。  相似文献   

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The open-circuit potential of 1100-alloy aluminium oscillates inca. 100°C solutions of 0.001–0.0007M PdCl2 in 4–10M HNO3, 0.0001M AgNO3 in 3M HNO3, 0.0002M Hg(NO3)2 in 3M HNO3, and 0.0001M Hg(SO4) in 1.5M (COOH)2.  相似文献   

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<正>英国曼彻斯特大学物理学家安德烈·海姆和康斯坦丁·诺沃肖洛夫于2004年成功地从石墨中剥离出石墨烯,并表征了它的性质,两人也因"在二维石墨烯材料的开创性实验",共同获得2010年诺贝尔物理学奖。石墨烯,因其拥有独特的物理性能而被广泛关注。它是目前世界上已知最薄、最坚硬、导电性和导热  相似文献   

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Of the various methods available for high‐performance liquid chromatography separation of enantiomers (of e.g. amino acids and amino group containing compounds) by the pre‐column derivatization approach, use of Marfey’s reagent has been most successful with continued application since its introduction in 1984. The reagent is prepared from difluoro dinitro benzene by nucleophilic substitution of one of its F atoms by l‐ alanine amide. There is flexibility to prepare several chiral variants (by substituting the F atom with different chiral auxiliaries) and to tailor the hydrophobicity and resolution, ultimately, of the diastereomeric derivatives. The present paper assesses and reviews applications of Marfey’s reagent and its chiral variants (i.e. other FDNP reagents) for enantioseparation of certain amino group containing drugs/amino acids, and to provide some case studies on enantiomeric separations that are important for the pharmaceutical industry. Various explanations for separation mechanism and elution order using FDNP reagents are included and the question of the configuration of the corresponding enantiomer using an indirect approach has also been addressed.  相似文献   

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正功能纳米材料是化学、物理、生物和材料科学多学科交叉的前沿,是纳米科技发展的基础。功能纳米材料集中体现了小尺寸、精准控制、高集成度和强相互作用等现代科学技术发展的特点,是将量子力学效应工程化或技术化的最好载体之一,呈现独特的光、电、磁、机械和催化等性质,在物理、生物、化学和材料学领域中都有广泛的研究和应用前景。  相似文献   

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Poly(anhydride-ester)s and poly(anhydride-amide)s derived from both 4- and 5-aminosalicylate acids (4- and 5-ASA) were synthesized and characterized by physicochemical methods. Thermal and solubility characteristics directly correlated to the polymer backbone composition; polymers based on 5-ASA had greater solubilities in organic solvents than polymers based on 4-ASA, and the poly(anhydride-ester)s thermally decomposed at temperatures nearly 100 °C higher than the corresponding poly(anhydride-amide)s. The polymers were self-contained, controlled-release systems that combine the drug and controlled-release mechanism into the polymer backbone. The erosion and degradation characteristics of the polymers were measured in physiologically relevant media. All polymer matrices fully degraded in media buffered to pH 7.4, whereas in acidic media (pH 1.2), all polymer matrices maintained greater than 50% mass over a 90-day time period. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3667–3679, 2003  相似文献   

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