An expression to describe the force that a chemical bond exerts on its terminal atoms is proposed, and is used to derive expressions for the bond force constant and bond compressibility. The unknown parameter in this model, the effective charge on the atoms that form the bond, is determined by comparing the derived force constants with those obtained spectroscopically. The resultant bond compressibilities are shown to generally agree well with those determined from high-pressure structure determinations and from the bulk moduli of high-symmetry structures. Bond valences can be corrected for pressure by recognizing that the bond-valence parameter, R(0), changes with pressure according to the equation dR(0)/dP = 10(-4) R(04)/(1/B-2/R(0) AA GPa (-1).
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http://dx.doi.org/10.1107/s0108768103010474 | DOI Listing |
Best Pract Res Clin Anaesthesiol
December 2023
Sydney Medical School, University of Sydney, Royal North Shore Hospital, Pacific Highway, St Leonards, NSW 2065, Australia. Electronic address:
Patient Blood Management evolved in recent years, focusing on the haematopoietic system as relevant to all disciplines of medicine. The allogeneic blood supply chain travels from donation, to fractionation, preservation, and storage, to therapeutic, established treatments, or prophylactics for a wide range of medical conditions. This supply chain 'connects' altruistic blood donors to patients in need, symbolising a 'gift relationship', emphasising the empathetic bond between donor and recipient.
View Article and Find Full Text PDFLangmuir
January 2025
Department of Environmental Chemistry and Chemical Engineering, School of Advanced Engineering, Kogakuin University, 2665-1 Nakano, Tokyo, Hachioji 192-0015, Japan.
The two-dimensional interlayer space of layered materials has been highlighted due to their adsorption property, whose nanostructure in the water-immersed state is scarcely understood by experiment. Recent developments in molecular simulation have enabled researchers to investigate the interlayer structure, but water content is necessary for accurate modeling. In the present study, we proposed a theoretical method to estimate the saturated water content and adsorption selectivity of trichlorophenol and phenol in montmorillonite modified with hexadecyltrimethylammonium ions.
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January 2025
State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences Taiyuan 030001 China
The research and development of the green synthesis route of chemicals has become the focus of research in academia and industry. At present, the highly efficient oxidation of ethanol to acetaldehyde over non-precious metal catalysts under mild conditions is most promising, but remains a big challenge. Herein, the Mo-Sn oxide catalyst was designed to successfully realize low-temperature oxidation of ethanol to acetaldehyde, achieving an acetaldehyde selectivity of 89.
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January 2025
Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi Japan 466-8555
We recently proposed a concept of self-transformation from thermoplastic polyesters into vitrimers intermolecular bond exchange as the cross-linking reaction. Key was the use of polyesters bearing hydroxyl side groups, which were cross-linked without additional cross-linkers through intermolecular transesterification in the presence of a suitable catalyst. In our previous study, a linear polyester was synthesized as the starting polymer by reacting dithiol monomers containing ester bonds (2-SH) with diepoxy monomers (2-epoxy) a thiol-epoxy reaction, generating hydroxyl side groups along the polyester chain.
View Article and Find Full Text PDFFront Oncol
December 2024
Department of Neurosurgery, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, Sichuan, China.
Craniopharyngioma is a rare, benign tumor that originates from the pituitary stalk and extends along the pituitary-hypothalamic axis. It can have serious effects due to its location, affecting hormone regulation, vision, and other neurological functions. It is particularly rare and challenging to manage it during pregnancy due to the potential impacts on both maternal and fetal health, requiring careful, individualized treatment.
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