Surface plasmon resonance （SPR） sensors with spectral interrogation provide a high refractive index resolution, a large dynamic range and a fixed optical detection module. In this work, we propose a new spectral det...
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Surface plasmon resonance （SPR） sensors with spectral interrogation provide a high refractive index resolution, a large dynamic range and a fixed optical detection module. In this work, we propose a new spectral detection unit that uses only one spectrometer to measure the SPR spectrum from multiple sensing spots rapidly and serially without any mechanical movement. This spectral detection unit is designed based on a spatial light modulator （SLM） configured as a programmable optical aperture for the spectrometer. To demonstrate this concept, a five-channel SPR sensor was built based on the proposed multichannel detection unit and we evaluated the device performance using a refractive index test. The average device refractive index resolution was 1.4 × 10 -6 refractive index units （RIU）.
A new amphiphilic graft copolymer containing hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chains was synthesized via sequential atom transfer radical polymerization (ATRP) followed ...
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A new amphiphilic graft copolymer containing hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chains was synthesized via sequential atom transfer radical polymerization (ATRP) followed by selective hydrolysis of poly(methoxymethyl acrylate) backbone. Grafting-from strategy was employed to synthesize PMOMA-g-PVAc graft copolymer (M_w/M_n=1.64) via ATRP. The final PAA-g-PVAc amphiphilic graft copolymer was obtained by selective acidic hydrolysis of PMOMA backbone in acidic environment without affecting the side chains. The critical micelle concentrations (cmc) in aqueous media were determined by a fluorescence probe technique. The micelle morphologies were found to be spheres.
Magnetotransport measurements and x-ray photoemission spectroscopy were used to investigate the surface conductivity of ZnO. Near-surface downward band bending, consistent with electron accumulation, was found on the ...
Magnetotransport measurements and x-ray photoemission spectroscopy were used to investigate the surface conductivity of ZnO. Near-surface downward band bending, consistent with electron accumulation, was found on the polar and nonpolar faces of bulk ZnO single crystals. A significant polarity effect was observed in that the downward band bending was consistently stronger on the Zn-polar face and weaker on the O-polar face. The surface electron accumulation layer was found to significantly influence the electrical properties of high resistivity, hydrothermally grown bulk ZnO crystals at temperatures below 200 K, and is largely responsible for the anomalously low electron mobility reported for this material.
Heteroepitaxial growth of m -plane (10 1- 0) InN film on (100) -γ -LiAlO2 (LAO) substrate has been realized by plasma-assisted molecular-beam epitaxy. Surface treatment of LAO substrate plays an important role in con...
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The generation of arbitrarily shaped nonspherical laser-induced cavitation bubbles is demonstrated with a optical technique. The nonspherical bubbles are formed using laser intensity patterns shaped by a spatial light...
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The generation of arbitrarily shaped nonspherical laser-induced cavitation bubbles is demonstrated with a optical technique. The nonspherical bubbles are formed using laser intensity patterns shaped by a spatial light modulator using linear absorption inside a liquid gap with a thickness of 40 μm. In particular we demonstrate the dynamics of elliptic, toroidal, square, and V-shaped bubbles. The bubble dynamics is recorded with a high-speed camera at framing rates of up to 300 000 frames per second. The observed bubble evolution is compared to predictions from an axisymmetric boundary element simulation which provides good qualitative agreement. Interesting dynamic features that are observed in both the experiment and simulation include the inversion of the major and minor axis for elliptical bubbles, the rotation of the shape for square bubbles, and the formation of a unidirectional jet for V-shaped bubbles. Further we demonstrate that specific bubble shapes can either be formed directly through the intensity distribution of a single laser focus, or indirectly using secondary bubbles that either confine the central bubble or coalesce with the main bubble. The former approach provides the ability to generate in principle any complex bubble geometry.
PEG-g-poly(aspartamide-co-N,N-dimethylethylenediamino aspartamide)(PEG-DMEDA-PASP) was synthesized by two-step ring-opening reactions of polysuccinimide(PSI) with a-methoxy-x-amino-poly(ethylene glycol) and N,*** poly...
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PEG-g-poly(aspartamide-co-N,N-dimethylethylenediamino aspartamide)(PEG-DMEDA-PASP) was synthesized by two-step ring-opening reactions of polysuccinimide(PSI) with a-methoxy-x-amino-poly(ethylene glycol) and N,*** polymer structure was confirmed by 1H NMR and *** resultant PEG-DMEDA-PASP with ammonium glycyrrhizinate(AMG) could form polymeric micelles in aqueous *** results of transmission electron microscopy(TEM) and dynamic light scattering(DLS) measurements revealed that these polymeric micelles were spherical particles with a narrow diameter distribution and that their average diameter was ca.70 *** polymeric micelles had high-loading capacity(58%) and encapsulation efficiency(70%) for *** results of in vitro release experiments showed that these polymeric micelles possessed sustained-release effects,with a release rate of 25% within 3 h and 90% within 24 h.
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