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991.
The Structure of the Iodine Adduct of 2,3‐Dihydro‐1,3,4,5‐tetramethyl‐2‐methylenimidazole: Weak Interactions in a Linear CI2‐Fragment [1] Crystals of C36H69Cl2I7N8 ( 7 ) consisting of 3 equivalents of 6 , one equivalent of pentamethylimidazolium iodide and one equivalent of dichloromethane are obtained through the crystallisation of the iodine adduct of 2,3‐dihydro‐1,3,4,5‐tetramethyl‐2‐methylenimidazole (C8H14I2N2, 6 ). The crystal structure analysis of 7 reveals the presence of weak I–I bond and a nearly linear C–I–I arrangement for 6 indicating an interionic charge transfer interaction between iodomethylimidazolium and iodide ions. 相似文献
992.
Norbert Kuhn Martin Grathwohl Christiane Nachtigal Manfred Steimann Gerald Henkel 《无机化学与普通化学杂志》2001,627(9):2039-2041
[{C8H12Rh}3(μ3‐OH)2]SbF6: A New Organometallic Rhodium Complex with Rh3O2 Core Crystals of C24H38F7O2Rh3Sb ( 3 ) obtained from the crystallisation of 2 from wet solvents consist of [{C8H12Rh}3(μ3‐OH)2]+ cations connected with the SbF6– anions via hydrogen bonds. In the cations, the Rh3 faces are bicapped by OH– ligands. 相似文献
993.
994.
Li J Burgett AW Esser L Amezcua C Harran PG 《Angewandte Chemie (International ed. in English)》2001,40(24):4776-4776
995.
Acrylic groups containing phosphonic acids were synthesized by ether formation of ethyl α‐chloromethylacrylate with hydroxyalkyl phosphonates and subsequent hydrolysis to the corresponding phosphonic acid α‐methylsubstituted acrylates. Furthermore, phosphonic acids derived from acrylonitrile and acrylamide were synthesized. The monomers are hydrolytically stable in aqueous ethanol. The radical polymerization of the monofunctional phosphonic acids results in water soluble polymers, whereas in case of a phosphonic acid diacrylate a cross‐linked polymer was formed. The most radical polymerizable phosphonic acids can be used to promote the adhesion to dentin. 相似文献
996.
Corrosion of Brass and Bronze by Ammonium Halides The intermetallic phases brass (Cu/Zn) and bronze (Cu/Sn) are corroded by ammonium fluoride and chloride, NH4F and NH4Cl, through selective oxidation of the less noble component zinc and tin, respectively. Copper is recrystallized as cube‐like or tabular single crystals under the respective influence of fluoride and chloride. Zinc and tin are incorporated in complex compounds of which (NH4)ZnF3, (NH4)2ZnF4, Zn(NH3)2Cl2 and (NH4)3SnF7 were detected by X‐ray powder diffraction. 相似文献
997.
998.
This is a broad overview and critical review of a particular group of closely related ex vivo and in vitro metabolic NMR spectroscopic methods. The scope of interest comprises studies of cultured cells and excised tissue, either intact or after physicochemical extraction of metabolites. Our detailed discussion includes pitfalls that have led to erroneous statements in the published literature, some of which may cause serious problems in metabolic and biological interpretation of results. To cover a wide range of work from relevant research areas, we consider not only the most recent achievements in the field, but also techniques that proved to be valid and successful in the past, although they may not have generated a very significant number of papers more recently. Thus, this comparative review also aims at providing background information useful for judiciously choosing between the metabolic ex vivo/in vitro NMR methods presented. Finally, the methods of interest are discussed in the context of, and in relation to, other metabolic analysis protocols such as HR-MAS and cell perfusion NMR, as well as the mass spectrometry approach. 相似文献
999.
Andrej Thurzo Viera Jan
ovi
ov Miroslav Hain Milan Thurzo Bohuslav Novk Helena Kosn
ov Viera Lehotsk Ivan Varga Peter Kov
Norbert Moravanský 《Molecules (Basel, Switzerland)》2022,27(13)
(1) Teeth, in humans, represent the most resilient tissues. However, exposure to concentrated acids might lead to their dissolving, thus making human identification difficult. Teeth often contain dental restorations from materials that are even more resilient to acid impact. This paper aims to introduce a novel method for the 3D reconstruction of dental patterns as a crucial step for the digital identification of dental records. (2) With a combination of modern methods, including micro-computed tomography, cone-beam computer tomography, and attenuated total reflection, in conjunction with Fourier transform infrared spectroscopy and artificial intelligence convolutional neural network algorithms, this paper presents a method for 3D-dental-pattern reconstruction, and human remains identification. Our research studies the morphology of teeth, bone, and dental materials (amalgam, composite, glass-ionomer cement) under different periods of exposure to 75% sulfuric acid. (3) Our results reveal a significant volume loss in bone, enamel, dentine, as well as glass-ionomer cement. The results also reveal a significant resistance by the composite and amalgam dental materials to the impact of sulfuric acid, thus serving as strong parts in the dental-pattern mosaic. This paper also probably introduces the first successful artificial intelligence application in automated-forensic-CBCT segmentation. (4) Interdisciplinary cooperation, utilizing the mentioned technologies, can solve the problem of human remains identification with a 3D reconstruction of dental patterns and their 2D projections over existing ante-mortem records. 相似文献
1000.