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1.
Professor Lou Massa’s contributions since the late 1960s to the founding of the field now known as “ Quantum Crystallography” (QCr) are briefly described. The term itself has been coined in 1995 by L. Huang, L. Massa, and J. Karle (1985 Nobel Laureate in Chemistry). Originally, QCr referred to the Clinton-Massa’s iterative approach that, for the first time, delivered N-representable electron densities that are consistent with the observed structure factors . These densities satisfy, at once, experimental observation and the necessarily underlying quantum mechanical requirement of being derived from an antisymmetric wavefunction. The single-determinantal quantum mechanical structure Huang, Massa, and Karle (HMK) imposed in their original work can be extended to any method that uses MOs including CI or DFT, as they demonstrate in their papers. HMK use the Clinton-Massa method to reconstruct approximations to the first order reduced density matrix of large molecules in a piecemeal manner from computationally-tractable fragments. The idea was also adapted by J. Hernández Trujillo and R. F. W. Bader in the context of the Quantum Theory of Atoms in Molecules (QTAIM). Massa et al. simplified and generalized this fragmentation method into what came to be known as the “ Kernel Energy Method” (KEM) which delivers the properties of large molecules accurately, at a fraction of the computational time, and within any model chemistry as applications to DNA, tRNA, the proto-ribosome, insulin, and graphene, amply demonstrate. Lou Massa has also pushed the envelope in other directions as well. In 1992, he and W. Lipscomb (1976 Nobel Laureate in Chemistry) published several papers predicting the structure and stability of Boron nanotubes and boron fullurene 12 years before they were eventually synthesized in laboratories at Yale and at Brookhaven. More recently, in 2006 L. Massa, J. Karle, and A. Yonath (2009 Nobel Laureate in Chemistry) (MKY) proposed a startling alternative to the then widely-accepted mechanism of the peptide bond formation in the active site of the ribosome. In sharp contrast with the accepted “ shuttle mechanism”, MKY’s “ direct” mechanism is simpler and, importantly, reproduces the measured thermodynamic and kinetic parameters. Massa has also contributed to other domains, for example interstellar chemistry, and to the policy, history, and philosophy of science. His TV program and Oxford University Press book (both titled “ Science and the Written Word”) represent an invaluable and candid documentation of some of the key discoveries in the words of a dozen Nobel Laureates and a constellation of scholars representing the Who’s Who of current science. It is with both admiration and affection that this paper (and this issue) is dedicated to Lou Massa, the person and the scientist. 相似文献
2.
<正>The new version of Journal of Energy Chemistry(JEC)has come this year.With this new form,our editorial team wishes to bring a better service to energy related research,particularly to colleagues in the field of energy chemistry.I hope these changes would be welcomed by you. 相似文献
4.
A 31-year-old letter from Professor Richard F. W. Bader to Professor Lou Massa outlining the connections between the quantum theory of atoms in molecules (QTAIM) and density functional theory (DFT) especially with regard to the first Hohenberg-Kohn theorem is brought to light. This connection has not often been the topic of such a focused review by Bader and is presented here for the first time. The scientific importance of this letter is, in the opinion of the presenter, as timely today as it was back then in 1986. In Bader’s own opening words: “... that if I sent you a summary of what I think are the important connections between our work and density functional theory, ...”. He then takes us in a grand tour of the foundations of QTAIM culminating into the antecedents of a paper he later published with Professor Pierre Becker, whereby the Hohenberg-Kohn theorem is shown to operate at the level of an atom-in-a-molecule. Bader closes his letter by suggesting to Massa: “Study these two charge distributions – they are proof of the theorem of Hohenberg and Kohn”. By that Bader meant that when the charge distributions of two atoms or groups are identical within a given precision, then the kinetic and total energy contributions of these atoms to the corresponding molecular quantities are also identical. It is revealing to follow the intellectual threads weaved by Bader which provides us with a glimpse of his thought processes and intuition that guided him to some of his key discoveries. The lucidity, rigor, and clarity characteristic of Bader and the informality of style of a letter makes it of pedagogic and historic interest. 相似文献
6.
As a representative of traditionally fermented Chinese medicine, Massa Medicata Fermentata (MMF) shows the functions of invigorating the spleen and stomach and promoting digestion, which plays an important role in the treatment of gastrointestinal diseases. The fermentation mechanism and the key factors that affect the quality of MMF have not been revealed yet, which has become an urgent issue that limits its clinical application. This article aims to systematically and comprehensively reveal the transformation of physical properties and the dynamic trend of chemical components including substrate components, volatile components, and lactic acid as anaerobic fermentation product during MMF fermentation. Along with obvious hyphae growth observed for MMF, the weight of MMF decreased, and the moisture and temperature increased. Through the quantified 14 components from substrate, ferulic acid increased from 45.53 ± 6.94 to 141.89 ± 78.40 μg/g, while glycosides and phenolic acids declined except caffeic acid. Also, within the 66 volatile components analyzed, alcohols and acids increased, while aldehydes and ketones decreased. Lactic acid was not detected in the fermentation substrate, but an apparent increase in lactic acid content was observed along with the increased fermentation days, resulting in 2.54 ± 0.15 mg/g on day 8. Based on the tested components, the fermentation process of MMF was discriminated into three distinct stages by principal component analysis, and an optimal fermentation time of four days was proposed. The results of this study will be of great significance to clarify the characteristics of fermentation and conduce to improving quality standards of MMF. 相似文献
9.
本专辑围绕电催化及燃料电池,收录了在相关研究领域具有丰富积累和影响的团队所撰写的 7 篇相关研究论文和综述,部分反映了我国在电催化剂的设计、合成方法和性能研究方面的研究进展,希望借助该专辑的出版,能使广大读者更深入地了解我国在这一领域的研究现状、研究趋势和存在的问题及挑战,推动我国电催化化学及新型燃料电池研究的进一步发展 相似文献
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Chinese Journal of Polymer Science - 相似文献
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Chinese Journal of Polymer Science - 相似文献
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