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71.
Singh Y Stoermer MJ Lucke AJ Guthrie T Fairlie DP 《Journal of the American Chemical Society》2005,127(18):6563-6572
A major chemical challenge is the structural mimicry of discontinuous protein surfaces brought into close proximity through polypeptide folding. We report the design, synthesis, and solution structure of a highly functionalized saddle-shaped macrocyclic scaffold, constrained by oxazoles and thiazoles, supporting two short peptide loops projecting orthogonally from the same face of the scaffold. This structural mimetic of two interhelical loops of cytochrome b(562) illustrates a promising approach to structurally mimicking discontinuous loops of proteins. 相似文献
72.
D. Acel A. Hahn M. Richter-Quittner J. K. Parnas R. Wagner R. Wodon O. Folin H. Bierry L. Moquet C. M. Wilhelmj E. Ponder W. Autenrieth H. Taege P. Cristol F. Utz G. E. Youngburg J. Munich L. Michaelis M. Maeda F. Fonseca Pincussen A. T. Merril H. Lucke J. C. Bock und M. Gilbert 《Fresenius' Journal of Analytical Chemistry》1926,69(7-8):314-320
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73.
Pedro Carlos de Oliveira Adriano Marim de Oliveira Jayne Carlos de Souza Barboza Amilton Martins dos Santos 《European Polymer Journal》2005,41(8):1883-1892
On the basis of the proposal that cumene hydroperoxide (CHP) in the presence of the base tetraethylenepentamine (TEPA) can form radicals by the abstraction reaction over addition to allylic double bonds, the efficiency of grafting monomers of methyl methacrylate (MMA) and dimethylaminoethylmethacrylate (DMAEMA) on to natural rubber (NR) has been studied. Seeded emulsion polymerization was used to graft such monomers. Different concentrations of each monomer have been examined. The effects of the concentrations of the monomers were evaluated by 1H NMR spectroscopy and Transmission Electron Microscopy (TEM). There is good evidence for the formation of graft copolymers of modified NR under the core-shell morphology as well as satisfactory efficiency of grafting in the presence of high concentrations of both monomers. At lower concentrations the grafting were not significant. The images of the morphology was obtained by Transmission Electron Microscopy after the preparation of the samples by cryo-sectioning and chemical fixation techniques. 相似文献
74.
Design and Synthesis of New Hybrid Molecules That Activate the Transcription Factor Nrf2 and Simultaneously Release Carbon Monoxide
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Dr. Jayne Louise Wilson Sarah Fayad Kobeissi Dr. Souhila Oudir Dr. Benjamin Haas Dr. Brian Michel Prof. Jean‐Luc Dubois Randé Dr. Anthony Ollivier Prof. Thierry Martens Dr. Michael Rivard Dr. Roberto Motterlini Dr. Roberta Foresti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14698-14704
75.
The kinetics of the ring‐opening reactions of the 3‐isothiazolones ( 1a–d ) with aqueous 2‐methyl‐2‐propanethiol has been explored at pH 4. The results strongly suggest that the reaction is second order in thiol and third order overall. Extrapolation of the kinetic data gives third‐order rate constants that lie in the order ( 1a ) > ( 1b ) > ( 1c ) > ( 1d ) in line with the known biological activity of these derivatives. The mechanism of the reaction is thought to involve attack by one thiol at the sulfur atom of the isothiazolone with the concomitant hydrogen bonding of a second thiol to the amide nitrogen. Calculations of the structure and electronic properties of the isothiazolones at the RHF 6‐31G** level are supportive. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 254–260, 2005 相似文献
76.
77.
Comprehensive Gas Chromatography-Time-of-Flight Mass Spectrometry (GC×GC-TOFMS) methodology has been refined for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in samples with different matrices. This is specifically for application in developing countries where access to gas chromatography-high resolution mass spectrometry (GC-HRMS) and highly skilled personnel is limited. The method, using an Rxi-5 Sil MS column in the first dimension ((1)D) coupled with an Rtx-200 column in the second dimension ((2)D), was used to quantify PCDDs and PCDFs in different environmental sample matrices. The results were compared with those obtained using GC-HRMS and good agreement was observed. The limit of detection (LOD) for the method (300fg on column for spiked soil samples) was determined using an Rxi-XLB ((1)D) column coupled with an Rtx-200 column ((2)D). Preliminary South African sample results are also discussed. Isomer specificity for different tetrachloro dibenzo-p-dioxins (TCDDs) and tetrachloro dibenzofurans (TCDFs) was investigated using a commercial standard. Adequate resolution was achieved. The method as described has great attraction for developing countries being both financially and operationally favourable. 相似文献
78.
Lucke K Lepper PA Blanchet MA Siebert U 《The Journal of the Acoustical Society of America》2011,130(5):3406-3412
In December 2005 construction work was started to replace a harbor wall in Kerteminde harbor, Denmark. A total of 175 wooden piles were piled into the ground at the waters edge over a period of 3 months. During the same period three harbor porpoises were housed in a marine mammal facility on the opposite side of the harbor. All animals showed strong avoidance reactions after the start of the piling activities. As a measure to reduce the sound exposure for the animals an air bubble curtain was constructed and operated in a direct path between the piling site and the opening of the animals' semi-natural pool. The sound attenuation effect achieved with this system was determined by quantitative comparison of pile driving impulses simultaneously measured in front of and behind the active air bubble curtain. Mean levels of sound attenuation over a sequence of 95 consecutive pile strikes were 14 dB (standard deviation (s.d.) 3.4 dB) for peak to peak values and 13 dB (s.d. 2.5 dB) for SEL values. As soon as the air bubble curtain was installed and operated, no further avoidance reactions of the animals to the piling activities were apparent. 相似文献
79.
Akihito Soeda Paweł Kurzyński Ravishankar Ramanathan Andrzej Grudka Jayne Thompson Dagomir Kaszlikowski 《Physics letters. A》2013
We show that sharp measurements of total magnetization cannot be used to reveal contextuality in macroscopic many-body systems of spins of arbitrary dimension. We decompose each such measurement into set of projectors corresponding to well-defined value of total magnetization. We then show that such sets of projectors are too restricted to construct Kochen–Specker sets. 相似文献