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991.
Stimuli-responsive polymer hydrogels as a new class of draw agent for forward osmosis desalination 总被引:1,自引:0,他引:1
Li D Zhang X Yao J Simon GP Wang H 《Chemical communications (Cambridge, England)》2011,47(6):1710-1712
Ionic polymer hydrogels with thermal responsive units are found to induce higher water permeation rates in the osmosis process, and higher water release rates under a combination of pressure and thermal stimuli. These hydrogels have the potential for use as draw agent in forward osmosis desalination. 相似文献
992.
Fortman GC Jacobsen H Cavallo L Nolan SP 《Chemical communications (Cambridge, England)》2011,47(34):9723-9725
The catalytic activity of a series of coordinatively unsaturated NHC-M(III) (M = Rh, Ir; NHC = N-heterocyclic carbene) complexes was tested in the deuteration of secondary and tertiary silanes. Among these, [IrCl(I(t)Bu')(2)] provides the highest conversions to the deuterated species. Mechanistic studies highlight the reversible nature of the ortho-metalation reaction. 相似文献
993.
A highly divergent synthesis of α-fuco-, α-6-deoxy-allo-, α-6-deoxy-altro-pyranosides has been achieved. This route utilizes a Wharton rearrangement as part of a new post-glycosylation transformation strategy. 相似文献
994.
Here we discuss some of the challenges of using dimers of spheres for SERS at long wavelengths. We show that the field enhancement in the gap between two spheres scales with a local surface plasmon metric, effectively limiting the range of wavelengths for which the largest SERS enhancements can be obtained for this class of structures to the near-IR. 相似文献
995.
Mihaela Badea Rodica Olar Valentina Uivarosi Dana Marinescu Victoria Aldea Stefania Felicia Barbuceanu George Mihai Nitulescu 《Journal of Thermal Analysis and Calorimetry》2011,105(2):559-564
Two new complexes having general formula VOL2·nH2O [(1) L: 5-hydroxyflavone, n = 1; (2) L: chrysin, n = 4] were synthesized and characterized. Based on IR and electronic data we concluded that studied flavones act as bidentate
ligands in complexes with metallic ion coordinated in a square-pyramidal stereochemistry. The thermal analysis (TG, DTA) elucidated
the composition and also the number and nature of the water molecules. The thermal behavior also indicated strong interactions
between oxovanadium (IV) and these oxygen donor ligands. 相似文献
996.
997.
Soft robotics for chemists 总被引:3,自引:0,他引:3
Ilievski F Mazzeo AD Shepherd RF Chen X Whitesides GM 《Angewandte Chemie (International ed. in English)》2011,50(8):1890-1895
998.
999.
Birgit Graf‐Zeiler Prof. Dr. Rainer H. Fink Prof. Dr. George Tzvetkov 《Chemphyschem》2011,12(18):3503-3509
Direct, real‐time analytical techniques that provide high‐resolution information on the chemical composition and submicrometer structure of various polymer micro‐ and nanoparticles are in high demand in a range of life science disciplines. Synchrotron‐based scanning transmission X‐ray microspectroscopy (STXM) combines both local‐spot chemical information (assessed via near‐edge X‐ray absorption fine structure spectroscopy) and imaging with resolution of several tens of nanometers, and thus can yield new insights into the nanoscale properties of these materials. Furthermore, this method allows in situ examination of soft‐matter samples in aqueous/gaseous environments and under external stimuli, such as temperature, pressure, ultrasound, and light irradiation. This Minireview highlights some recent progress in the application of the STXM technique to study the temperature‐dependent behavior of polymer core–shell microcapsules and to characterize the physicochemical properties of the supporting shells of gas‐filled microbubbles in their natural hydrated state. 相似文献
1000.
Bravo I Díaz-de-Mera Y Aranda A Moreno E Nutt DR Marston G 《Physical chemistry chemical physics : PCCP》2011,13(38):17185-17193
Density Functional Theory (DFT) has been used with an empirically-derived correction for the wavenumbers of vibrational band positions to predict the infrared spectra of several fluorinated esters (FESs). Radiative efficiencies (REs) were then determined using the method of Pinnock et al. and these were used with atmospheric lifetimes from the literature to determine the direct global warming potentials of FESs. FESs, in particular fluoroalkylacetates, alkylfluoroacetates and fluoroalkylformates, are potential greenhouse gases and their likely long atmospheric lifetimes and relatively large REs, compared to their parent HFEs, make them active contributors to global warming. Here, we use the concept of indirect global warming potential (indirect GWP) to assess the contribution to the warming of several commonly used HFEs emitted from the Earth's surface, explicitly taking into account that these HFEs will be converted into the corresponding FESs in the troposphere. The indirect GWP can be calculated using the radiative efficiencies and lifetimes of the HFE and its degradation FES products. We found that the GWPs of those studied HFEs which have the smallest direct GWP can be increased by 100-1600% when taking account of the cumulative effect due to the secondary FESs formed during HFE atmospheric oxidation. This effect may be particularly important for non-segregated HFEs and some segregated HFEs, which may contribute significantly more to global warming than can be concluded from examination of their direct GWPs. 相似文献