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131.
132.
Jeroen DeNeve Joris J. Haven Simon Harrisson Tanja Junkers 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):14007-14011
The separation of an oligo(methyl acrylate) distribution, obtained from reversible addition–fragmentation chain transfer (RAFT) polymerization, in a discrete (dispersity=1) oligomeric library (degree of polymerization between 1 and 22) is presented. The properties of this library in terms of diffusivity, glass transition temperature, and viscosity are determined, filling a significant knowledge gap associated with these materials. The obtained oligomer library is used to construct artificial oligomer distributions on demand. These artificial oligomer distributions are used to highlight the potential to tailor physical properties of a material, while concomitantly demonstrating the limitations associated with size‐exclusion chromatography analysis of molecular weight and dispersity in particular. 相似文献
133.
Guaiacol, pyrocatechol and resorcinol, were isolated and quantified as the major products from catalytic pyrolysis of lignin of various origin. The novel procedure utilises formic acid as the hydrogen source in combination with a palladium catalyst and Nafion® SAC-13 as a solid acid catalyst with water as reaction medium. The reaction is conducted at moderate pyrolysis temperature and short reaction time. Several palladium based catalysts and different types of lignin were investigated. The lignins and the model compounds demonstrated various chemical behaviour, under identical reaction conditions; various phenols were formed from the lignins, while the model compounds were hydrodeoxygenated, demethylated and demethoxylated. 相似文献
134.
Thomas Luxbacher Mirjana Čurlin Irena Petrinić Hermina Bukšek Tanja Pušić 《Cellulose (London, England)》2014,21(5):3829-3839
Raw cotton knitted fabrics of Greek, Indonesian, and Indian origin were investigated through surface characterization before and after processing. Surface modifications of all the knitted cotton fabrics were objectively evaluated through zeta potential measurements within a range of the electrolyte solution pHs, and swelling over time. Streaming potential coefficients of different cotton knitted fabrics were applied in order to establish a correlation between the properties of the raw and treated cotton knitted fabrics of different origins. The rate of swelling was calculated from the streaming potential coefficients of the raw knitted fabrics before and after different treatments. Swelling rate for different origins and different treatments of cotton knitted fabrics and the correlation coefficients were obtained using linear regression. Additionally, a data cluster analysis was performed in order to group different origins of cotton, while all the treatments were sorted according to zeta potential and the rate of swelling coefficients. The obtained results showed differences among the clusters, depending on the origin of the cotton knitted fabrics and treatments they were exposed to. 相似文献
135.
We consider subordinators in the domain of attraction at 0 of a stable subordinator (where ); thus, with the property that , the tail function of the canonical measure of , is regularly varying of index as . We also analyse the boundary case, , when is slowly varying at 0. When , we show that converges in distribution, as , to the random variable . This latter random variable, as a function of , converges in distribution as to the inverse of an exponential random variable. We prove these convergences, also generalised to functional versions (convergence in ), and to trimmed versions, whereby a fixed number of its largest jumps up to a specified time are subtracted from the process. The case produces convergence to an extremal process constructed from ordered jumps of a Cauchy subordinator. Our results generalise random walk and stable process results of Darling, Cressie, Kasahara, Kotani and Watanabe. 相似文献
136.
Bogdan I. Florea Martijn Verdoes Nan Li Wouter A. van der Linden Paul P. Geurink Hans van den Elst Tanja Hofmann Arnoud de Ru Peter A. van Veelen Keiji Tanaka Katsuhiro Sasaki Shigeo Murata Hans den Dulk Jaap Brouwer Ferry A. Ossendorp Alexei F. Kisselev Herman S. Overkleeft 《Chemistry & biology》2010,17(8):795-801
137.
138.
Carina Lemke Dr. Adéla Jílková Dominic Ferber Dr. Annett Braune Anja On Dr. Patrick Johe Dr. Alena Zíková Prof. Dr. Tanja Schirmeister Dr. Michael Mareš Dr. Martin Horn Prof. Dr. Michael Gütschow 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(62):e202201636
Rhodesain is the major cysteine protease of the protozoan parasite Trypanosoma brucei and a therapeutic target for sleeping sickness, a fatal neglected tropical disease. We designed, synthesized and characterized a bimodal activity-based probe that binds to and inactivates rhodesain. This probe exhibited an irreversible mode of action and extraordinary potency for the target protease with a kinac/Ki value of 37,000 M−1s−1. Two reporter tags, a fluorescent coumarin moiety and a biotin affinity label, were incorporated into the probe and enabled highly sensitive detection of rhodesain in a complex proteome by in-gel fluorescence and on-blot chemiluminescence. Furthermore, the probe was employed for microseparation and quantification of rhodesain and for inhibitor screening using a competition assay. The developed bimodal rhodesain probe represents a new proteomic tool for studying Trypanosoma pathobiochemistry and antitrypanosomal drug discovery. 相似文献
139.
Weil T Vosch T Hofkens J Peneva K Müllen K 《Angewandte Chemie (International ed. in English)》2010,49(48):9068-9093
This Review summarizes the latest advances in the field of rylene dyes and rylene nanoemitters for applications in photonics, and describes the influence of the dye design on the optical properties, the self-assembly, the molecular interactions, as well as the labeling specificity of the compounds. The interplay between tailored (macro)molecular design and bulk/single-molecule spectroscopy enables complex processes to be explained, for example, the kinetics of energy-transfer processes or (bio)catalysis. Such investigations are essential for the ultimate design of optimized nanoemitters, and require a close cooperation between spectroscopists and preparative organic chemists. 相似文献
140.
Hashmi AS Weyrauch JP Kurpejović E Frost TM Miehlich B Frey W Bats JW 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(22):5806-5814
The effect of different substituents, such as bromo, chloromethyl, hydroxymethyl, formyl, acetyl, carboxy, and acylated hydroxymethyl and ammonium groups, on the furan ring of substrates in gold-catalyzed phenol synthesis has been investigated. The furan ring was also replaced by different heterocycles, such as pyrroles, thiophenes, oxazoles, and a 2,4-dimethoxyphenyl group; gold catalysis then delivered no phenols, but occasionally other products were obtained. [Ru(3)(CO)(12)] also catalyzed the conversion of 1 at a low rate, [Os(3)(CO)(12)] failed as a catalyst, and with [Co(2)(CO)(8)] the alkyne complex 19 can be obtained, it does not lead to any phenol but reacts with norbornene to give the product of a Pauson-Khand reaction. Efforts to prepare vinylidene complexes of 1 provided the only evidence for these species; in the presence of a phosphane ligand with ruthenium an interesting deoxygenation to 22 was observed. The phenol 2 c was converted to the allyl ether, a building block for para-Claisen rearrangements, and to the aryl triflate, a building block for cross-coupling reactions. 相似文献