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51.
Iaroshenko VO Bunescu A Spannenberg A Supe L Milyutina M Langer P 《Organic & biomolecular chemistry》2011,9(21):7554-7558
The reaction of 1,3-bis-silyl enol ethers with 3-methoxalylchromones affords a great variety of functionalised 2,4'-dihydroxybenzophenones. These products are formed by a domino Michael/retro-Michael/Mukaiyama-aldol reaction. The synthesized compounds are promising candidates for the synthesis of the novel UV-A/B and UV-B filters. 相似文献
52.
Walther J Gaertner M Cimalla P Burkhardt A Kirsten L Meissner S Koch E 《Analytical and bioanalytical chemistry》2011,400(9):2721-2743
Optical coherence tomography (OCT) is a noninvasive, high-resolution, interferometric imaging modality using near-infrared
light to acquire cross-sections and three-dimensional images of the subsurface microstructure of biological specimens. Because
of rapid improvement of the acquisition speed and axial resolution of OCT over recent years, OCT is becoming increasingly
attractive for applications in biomedical research. Therefore, OCT is no longer used solely for structural investigations
of biological samples but also for functional examination, making it potentially useful in bioanalytical science. The combination
of in vivo structural and functional findings makes it possible to obtain thorough knowledge on basic physiological and pathological
processes. Advanced applications, for example, optical biopsy in visceral cavities, have been enabled by combining OCT with
established imaging modalities. This report gives an outline of the state of the art and novel trends of innovative OCT approaches
in biomedical research in which the main focus is on applications in fundamental research and pre-clinical utilization. 相似文献
53.
Jarre G Liang Y Betz P Lang D Krueger A 《Chemical communications (Cambridge, England)》2011,47(1):544-546
Stable covalent C-C bonding of aromatic moieties has been achieved using Diels-Alder reactions on surface-annealed nanodiamond. Subsequent functionalisation leads to tunable surface properties and molecule-like behaviour. 相似文献
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55.
Tobias Schulz Dr. Sebastian Ahrens Dirk Meyer Christoph Allolio Anke Peritz Prof. Dr. Thomas Strassner 《化学:亚洲杂志》2011,6(3):863-867
Owing to numerous new applications, the interest in “task‐specific” ionic liquids increased significantly over the last decade. But, unfortunately, the imidazolium‐based ionic liquids (by far the most frequently used cations) have serious limitations when it comes to modifications of their properties. The new generation of ionic liquids, called tunable aryl–alkyl ionic liquids (TAAILs), replaces one of the two alkyl chains on the imidazolium ring with an aryl ring which allows a large degree of functionalization. Inductive, mesomeric, and steric effects as well as potentially also π π and π π+ interactions provide a wide range of possibilities to tune this new class of ILs. We investigated the influence of electron‐withdrawing and ‐donating substituents at the para‐position of the aryl ring (NO2, Cl, Br, EtO(CO), H, Me, OEt, OMe) by studying the changes in the melting points of the corresponding bromide and bis(trifluoromethanesulfonyl)imide, (N(Tf)2−), salts. In addition, we calculated (B3LYP/6‐311++G(d,p)) the different charge distributions of substituted 1‐aryl‐3‐propyl‐imidazolium cations to understand the experimentally observed effects. The results indicated that the presence of electron‐donating and ‐withdrawing groups leads to strong polarization effects in the cations. 相似文献
56.
Isidoro Lpez Mehmed Z. Ertem Somnath Maji Jordi Benet‐Buchholz Anke Keidel Uwe Kuhlmann Peter Hildebrandt Christopher J. Cramer Victor S. Batista Antoni Llobet 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(1):209-213
The homogeneous catalysis of water oxidation by transition‐metal complexes has experienced spectacular development over the last five years. Practical energy‐conversion schemes, however, require robust catalysts with large turnover frequencies. Herein we introduce a new oxidatively rugged and powerful dinuclear water‐oxidation catalyst that is generated by self‐assembly from a mononuclear catalyst during the catalytic process. Our kinetic and DFT computational analysis shows that two interconnected catalytic cycles coexist while the mononuclear system is slowly and irreversibly converted into the more stable dinuclear system: an extremely robust water‐oxidation catalyst that does not decompose over extended periods of time. 相似文献
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58.
Seven diterpenoids, isolated due to their ability to inhibit spore germination in the plant pathogenic fungus Magnaporthe grisea, were obtained from cultures of the basidiomycete Coprinus heptemerus. The structures of the compounds, named heptemerones A-G, were determined with spectroscopic techniques. 相似文献
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60.
Tracy P. Houghton David N. Thompson J. Richard Hess Jeffrey A. Lacey Michael P. Wolcott Anke Schirp Karl Englund David Dostal Frank Loge 《Applied biochemistry and biotechnology》2004,113(1-3):71-93
Combining biologic pretreatment with storage is an innovative approach for improving feedstock characteristics and cost, but
the magnitude of responses of such systems to upsets is unknown. Unsterile wheat straw stems were upgraded for 12 wk with
Pleurotus ostreatus at constant temperature to estimate the variation in final compositions with variations in initial moisture and inoculum.
Degradation rates and conversions increased with both moisture and inoculum. A regression analysis indicated that system performance
was quite stable with respect to inoculum and moisture content after 6 wk of treatment. Scale-up by 150× indicated that system
stability and final straw composition are sensitive to inoculum source, history, and inoculation method. Comparative testing
of straw-thermoplastic composites produced from upgraded stems is under way. 相似文献