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991.
Davis JJ Coleman KS Busuttil KL Bagshaw CB 《Journal of the American Chemical Society》2005,127(38):13082-13083
Appropriately modified proximal probes can be utilized in the spatially resolved chemical coupling of surface-bound and solution-phase reagents. Herein we report a chemically specific Suzuki coupling reaction between a surface-confined aryl bromide and boronic acid reagents in solution achieved using a catalytic AFM probe. 相似文献
992.
Alkoxide-functionalized N-heterocyclic carbenes (NHCs) stabilise the potassium-imidazole-2-ylidene fragment against 1,2 alkyl rearrangement reactions; this allows the first structural characterisation of a potassium NHC complex, which reveals distorted and unusual bonding interactions between the imidazole ring and the potassium cation. 相似文献
993.
Ribot F Escax V Roiland C Sanchez C Martins JC Biesemans M Verbruggen I Willem R 《Chemical communications (Cambridge, England)》2005,(8):1019-1021
Complexation affinity of laurate ligands (C(12)H(23)O(2)) grafted onto the surface of cerium(IV) oxide nanoparticles can be probed and quantified in situ, by pulsed field gradient (1)H NMR through the dependence of the diffusion coefficient on the size of a species. 相似文献
994.
Two new 1-N-iminosugars have been prepared as hexofuranose analogues in an efficient manner by an RCM-based route. Both 3,4-disubstituted pyrrolidines display moderate inhibitory activity against Mycobacterium smegmatis galactan biosynthesis. [structure: see text] 相似文献
995.
The effects of steam sterilization and gamma-irradiation on chitosan and thermogelling chitosan-beta-glycerophosphate (GP) solutions containing polyol additives were investigated. The selected polyols were triethylene glycol, glycerol, sorbitol, glucose and poly(ethylene glycol) (PEG). They were incorporated to chitosan solutions prior to sterilization in a proportion ranging from 1 to 5% (w/v). The solutions were characterized with respect to their viscosity, thermogelling properties, compressive stress relaxation behavior and chitosan degradation. All polyols reduced the autoclaving-induced viscosity loss and had a positive impact on the solution thermogelling properties and compressive performance of the gels. Steam sterilization in the presence of glucose resulted in a substantial increase in the solution viscosity and gel strength. This was associated with a strong discoloration suggesting chemical alteration of the system. PEG was the most effective agent in preventing hydrolytic degradation of chitosan chains. Gamma-irradiation strongly decreased the chitosan solution viscosity regardless of the presence of additives, even when sterilization was carried out at -80 degrees C. Moreover, the thermogelling properties were dramatically altered, and thus, gamma-irradiation would not be an appropriate method to sterilize chitosan solutions. In conclusion, polyols are potentially useful additive to maximise the viscoelastic and mechanical properties of chitosan-GP after steam sterilization. 相似文献
996.
Bioelectrochemical single-walled carbon nanotubes 总被引:21,自引:0,他引:21
Azamian BR Davis JJ Coleman KS Bagshaw CB Green ML 《Journal of the American Chemical Society》2002,124(43):12664-12665
Metalloproteins and enzymes can be immobilized on SWNTs of different surface chemistry. The combination of high surface area, robust immobilization and inherent nanotube electrochemical properties is of promising application in bioelectrochemistry. 相似文献
997.
Taubman MS Myers TL Cannon BD Williams RM Capasso F Gmachl C Sivco DL Cho AY 《Optics letters》2002,27(24):2164-2166
We report a heterodyne beat with a linewidth of 5.6+/-0.6 Hz between two cavity-stabilized quantum-cascade lasers operating at 8.5 microm . We also present a technique for measuring this beat that avoids the need for extreme isolation of the optical cavities from the environment, that of employing a third servo loop with low bandwidth to force one cavity to track the slow drifts and low-frequency fluctuations of the other. Although it is not fully independent, this technique greatly facilitates heterodyne beat measurements for evaluating the performance of cavity-locked lasers above the bandwidth of the third loop. 相似文献
998.
999.
Claire Voisin 《Mathematische Annalen》1988,280(4):605-611
Sans résumé 相似文献
1000.