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151.
Three model drugs with different function groups were chosen to dialyze with dextran-graft-poly(N-isopropylacrylamide).Only ibuprofen could induce the formation of drug loaded micelles,which was confirmed with dynamic light scattering and transmission electron microscope.Hydrogen-bonding between the amide groups of poly(N-isopropylacrylamide) and the carboxyl groups of ibuprofen was driving force for the drug-loaded micelle.It was also found that the diameter of the ibuprofen-loaded micelles changed reversibly against temperature. 相似文献
152.
153.
The electrochemiluminescence (ECL) of luminol on indium tin oxide (ITO) glass was high even under a low potential around 0.4-0.5 V, which was quite different from other electrodes such as platinum. ITO nanoparticles were synthesized and used in the research on ITO glass in the ECL process. A static interaction between ITO and luminol is confirmed from UV-vis and fluorescence spectra. Then the ECL enhancement can be supposed to originate from the adsorption of luminol on ITO, which facilitated luminol’s oxidization to the excited state, giving out ECL. On the other hand, ITO can catalyze the generation of reactive oxygen species (ROSs), similar to some other nanomaterials, which also favored the ECL enhancement of luminol. 相似文献
154.
Hsin-Fu Shen Niann-Chern Lee Ming-Hsien Tu 《Theoretical and Mathematical Physics》2010,165(2):1456-1469
Based on the kernel formula proposed by Carroll and Kodama, we derive the dispersionless Hirota equations of the universal
Whitham hierarchy. We also verify the associativity equations in this hierarchy from the dispersionless Hirota equations and
give a realization of the associative algebra with the structure constants expressed in terms of residue formulas. 相似文献
155.
Simultaneous hyperaccumulation of arsenic and antimony in Cretan brake fern: Evidence of plant uptake and subcellular distributions 总被引:1,自引:0,他引:1
Arsenic (As) and antimony (Sb) show similar chemical properties and often present together in sulfide ores. Currently, phenomenon of co-contamination of As and Sb at some sites of the world has been increasingly emerged. The present study was conducted to explore the potential of Pteris cretica L. (Cretan brake fern), an arsenic (As) hyperaccumulator, to simultaneously accumulate As and Sb under hydroponic conditions. Arsenic was imposed at medium and high levels of 5 mg L− 1 and 20 mg L− 1, while Sb was imposed either single or co-presence with As at medium and high levels of 10 mg L− 1 and 20 mg L− 1, with no As and Sb addition as the control. The single and interactive effects of As and Sb on their uptake and subcellular distributions were analyzed. Cretan brake fern could accumulate high concentrations of As and Sb, with the highest concentrations of As and Sb been recorded as 1677.2 mg kg− 1 and 1516.5 mg kg− 1 in the fronds, respectively. Arsenic and Sb were found mainly in cytosol, while less in cell wall and cytoplasmic organelles. Sb uptake by Cretan brake fern was enhanced with increasing As levels, which was accompanied with an increase of Sb but a decrease of As in cytosol fractions. Arsenic uptake was slightly enhanced whereas suppressed when Sb was co-present in a medium and high level, respectively; however, in both conditions, As was found to be decreased in cytosol of the above ground parts as fronds and stems of Cretan brake fern. The results demonstrate Cretan brake fern can simultaneously hyperaccumulate As and Sb, thus is valued in phytoremediation of As and Sb co-contamination. 相似文献
156.
Guo-Ping Guo Xiao-Jie Hao Tao Tu Zhi-Cheng Zhu Guang-Can Guo 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(2):141-146
We propose a scheme to eliminate the effect of non-nearest-neighbor
qubits in preparing cluster state with double-dot molecules. As the
interaction Hamiltonians between qubits are Ising-model and mutually
commute, we can get positive and negative effective interactions
between qubits to cancel the effect of non-nearest-neighbor qubits
by properly changing the electron charge states of each quantum dot
molecule. The total time for the present multi-step cluster state
preparation scheme is only doubled for one-dimensional qubit chain
and tripled for two-dimensional qubit array comparing with the time
of previous protocol leaving out the non-nearest-neighbor
interactions. 相似文献
157.
Zhen-Han Tu 《Mathematische Zeitschrift》2002,240(1):13-35
We prove that any proper holomorphic mapping from to is necessarily a totally geodesic isometric embedding with respect to their Bergman metrics and therefore is the standard
linear embedding up to their automorphisms. The proof of the main result in this paper will be achieved by a differential-geometric
study of a special class of complex geodesic curves on the bounded symmetric domains with respect to their Bergman metrics.
Received: 31 October 2000; in final form: 2 July 2001/ Published online: 4 April 2002 相似文献
158.
159.
We demonstrate that base and sugar protons within a DNA oligomer can be assigned unambiguously following site-specific 15N,13C isotope incorporation at levels as low as 1% enrichment. This simple and cost-effective methodology is demonstrated on the d(GGGTTCAGG) DNA sequence, which forms a dimeric G-quadruplex containing G.G.G.G tetrads sandwiched between G.(C-A) triads. 相似文献
160.
We exploited Nd(3+) laser emission at 1061.9 nm ((4)F(3/2)?(4)I(11/2) channel) in a self-chi((2)) active GdAl(3)(BO(3))(4):Nd(3+) laser crystal. UV radiation was obtained from a 1.8% yield from self-sum-frequency mixing: 1/pump + 1/1061.9 = 1/UV, during pumping in the Nd(3+) (4)G(5/2)-(2)G(7/2) levels near 588 nm. The UV tunability had a range of 378-382 nm. We have demonstrated, for the first time to our knowledge, generation of coherent IR radiation from a self-difference-frequency mixing laser: 1/pump - 1/1061.9 = 1/IR. We got a 0.5% yield and tunability in the 1305-1365-nm range. 相似文献