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De Gussem K Vandenabeele P Verbeken A Moens L 《Analytical and bioanalytical chemistry》2007,387(8):2823-2832
Confocal Raman spectroscopy is a non-destructive analytical method which is useful to obtain detailed information about the
molecular composition of biological samples. Its high spatial resolution was used to collect spectra of single basidiospores
of macrofungi of the genera Collybia, Gymnopus, Laccaria, Lactarius, Mycena and Russula. These spectra can be divided into three major taxon-related groups, with general compositional differences, such as the
relative amount of lipids compared to proteins. In this study, collapsing of thin-walled spores during storage was often observed,
a phenomenon which has been given little attention in the literature. The Raman spectra are treated with different chemometric
preprocessing techniques, including Savitsky–Golay, standard normal variate (SNV) preprocessing and extended multiplicative
scatter correction (EMSC). By using linear discriminant analysis, approximately 90% of the spectra can be assigned to the
correct genus, but identification on the species level was not possible. 相似文献
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The phase-field method has already proven its usefulness to simulate microstructural evolution for several applications, e.g., during solidification, solid-state phase transformations, fracture, etc. This wide variety of applications follows from its diffuse-interface approach. Moreover, it is straightforward to take different driving forces into account. The purpose of this paper is to give an introduction to the phase-field modelling technique with particular attention for models describing phenomena important in extractive metallurgy. The concept of diffuse interfaces, the phase-field variables, the thermodynamic driving force for microstructure evolution and the phase-field equations are discussed. Some of the possibilities to solve the equations describing microstructural evolution are also described, followed by possibilities to make the phase-field models quantitative and the phase-field modelling of the microstructural phenomena important in extractive metallurgy, i.e., multiphase field models. Finally, this paper illustrates how the phase-field method can be applied to simulate several processes taking place in extractive metallurgy and how the models can contribute to the further development or improvement of these processes. 相似文献
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Strain promoted cycloaddition is presented as a tool for RNA conjugation on the solid phase; RNA-cyclooctyne conjugates are prepared by cycloaddition to both azide (strain-promoted azide-alkyne cycloaddition, SPAAC) and nitrile oxide dipoles (strain-promoted nitrile oxide-alkyne cycloaddition, SPNOAC). The conjugation is compatible with 2'-OMe blocks and with 2'-O-TBDMS protection on the ribose moieties of the sugar. Nitrile oxide dipoles are found to be more reactive click partners than azides. The conjugation proceeds within 10 min in aqueous solvents, at room temperature without any metal catalyst and tolerates dipoles of varying steric bulk and electronic demands, including pyrenyl, coumarin and dabcyl derivatives. 相似文献
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We herein describe the synthesis of furan containing peptides for further post-synthetic derivatisation in solution through our recently developed furan-oxidation-labeling technology. Previously, it was reported by others that during acidic cleavage of furan-modified peptides, furan moieties can suffer from degradation. We demonstrate here that this degradation is position dependent and can be fully suppressed through introduction of proximate aromatic residues. Versatile introduction of 2-furylalanine at internal, C-terminal as well as the sensitive N-terminal positions has now been proven possible. 相似文献
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Schepens W Van Haver D Vandewalle M Bouillon R Verstuyf A De Clercq PJ 《Organic letters》2006,8(19):4247-4250
A novel series of analogues of calcitriol (1) is developed featuring a spirocyclic central core resulting from C18/C21-connection and C15/C16-deletion (2a, 2b). The synthesis of the key intermediate involves an Eschenmoser rearrangement of an enantiomerically pure bromo-substituted cyclohexenol. 相似文献
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Singlet Oxygen‐Induced Furan Oxidation for Site‐Specific and Chemoselective Peptide Ligation 下载免费PDF全文
Eirini Antonatou Dr. Kurt Hoogewijs Dr. Dimitris Kalaitzakis Andreas Baudot Prof. Georgios Vassilikogiannakis Prof. Annemieke Madder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8457-8461
A novel chemoselective ligation methodology has been developed for the facile construction of peptide‐based fluorescent probes. Furan‐containing peptides were activated by singlet oxygen and covalently engaged by nitrogen nucleophiles to yield stable conjugates. Singlet oxygen was compatible with sensitive amino acid residues within the peptides and a range of fluorophores, bearing different functionalities, were successfully incorporated, illustrating the broad scope of the developed strategy. 相似文献