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91.
An innovative, powerful, efficient and relatively rapid method was developed to synthesise various β-aminoketone derivatives from cyclohexanone, substituted aromatic amines and aromatic or hetero-aromatic aldehydes via ultrasound-assisted
direct-type catalytic Mannich reaction using bismuth(III) triflate in water. Good yields of the desired β-aminoketones were obtained at room temperature by ultrasound-assisted reaction within 1–2 h. The major advantages of the
proposed method are undemanding conditions, easy operation, low toxicity, shorter reaction time, anti selectivity and higher
yields in comparison with conventional methods. 相似文献
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93.
Solid polymer electrolytes based on methyl cellulose (MC)-potato starch (PS) blend doped with ammonium nitrate (NH4NO3) are prepared by solution cast technique. The interaction between the electrolyte’s materials is proven by Fourier transform infrared (FTIR) analysis. The thermal stability of the electrolytes is obtained from thermogravimetric analysis (TGA). The room temperature conductivity of undoped 60 wt.% MC-40 wt.% PS blend film is identified to be (1.04 ± 0.19) × 10?11 S cm?1. The addition of 30 wt.% NH4NO3 to the polymer blend has optimized the room temperature conductivity to (4.37 ± 0.16) × 10?5 S cm?1. Conductivity trend is verified by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and dielectric analysis. Temperature-dependence of conductivity obeys Arrhenius rule. Conductivity is found to be influenced by the number density (n) and mobility (μ) of ions. From transference number measurements (TNM), ions are found to be the dominant charge carriers. 相似文献
94.
This paper reports on the characterization and application in proton batteries of corn starch-chitosan blend biopolymer electrolyte doped with NH4I as a proton provider. In this work, all electrolyte films are prepared by the solution cast method. Thermogravimetric analysis (TGA) reveals that the plasticized electrolyte is stable up to 180 °C. Differential scanning calorimetry (DSC) study shows that T g values decrease with the addition of salt and plasticizer. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analyses verify the conductivity results from a previous work. The cation transference number for the highest conducting electrolyte was 0.40. The highest conducting electrolyte has been used in fabrication of primary and secondary proton batteries. 相似文献
95.
In this rapid communication we describe a new approach to protein detection with chemiluminescence. By combining common practices in protein detection with chemiluminescence, microwave technology, and metal-enhanced chemiluminescence, we show that we can use low power microwaves to substantially increase enzymatic chemiluminescent reaction rates on metal substrates. As a result, we have found that we can in essence trigger chemiluminescence with low power microwave (Mw) pulses and ultimately, perform on-demand protein detection assays. Using microwave triggered metal-enhanced chemiluminescence (MT-MEC), we not only improve the sensitivity of immunoassays with enhanced signal-to-noise ratios, but we also show that we can accurately quantify protein concentrations by integrating the photon flux for discrete time intervals. 相似文献
96.
Kadir Esmer 《Applied Surface Science》2009,256(5):1548-1552
We present results for alkali metallization effects on photoluminescence (PL) properties of porous silicon (PS). The metallization of PS was realized by immersion plating in solutions containing 3 mM LiNO3, KNO3 and NaNO3 metal salts. The surface bond configuration of PS was monitored by Fourier transmission infrared spectroscopy (FTIR) and it was found that the PS surface was oxidized after metallization. Surface properties of PS were investigated by field emission scanning electron microscopy (FE-SEM) and it was found that the PS surface was covered by alkali metals for short immersion times. The PL intensity increased for critical immersion times and PL spectrum shifted to high energy region with the metallization. The experimental results suggest a possibility that the metallization provides a relatively easy way to achieve an increase in the PL intensity and oxidation of the PS surface. 相似文献
97.
Decomposition of Turbulent Velocity Fields in an SI Engine 总被引:3,自引:0,他引:3
In this study, the turbulence filter, the phase averaging and the proper orthogonal decomposition methods are used to decompose
experimentally measured turbulent velocity fields in an SI engine. The radial and circumferential turbulent velocity fields
were measured using hot wire anemometer under motored conditions at different engine configurations. The decomposed results
of each technique are compared with each other. In addition, the obtained organized and turbulence motions and their energy
spectra are examined. Finally, coherent structures of velocity fields and their activities are investigated.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
98.
99.
100.
Advances in Surface-Enhanced Fluorescence 总被引:4,自引:0,他引:4
Lakowicz JR Geddes CD Gryczynski I Malicka J Gryczynski Z Aslan K Lukomska J Matveeva E Zhang J Badugu R Huang J 《Journal of fluorescence》2004,14(4):425-441
We report recent achievements in metal-enhanced fluorescence from our laboratory. Several fluorophore systems have been studied on metal particle-coated surfaces and in colloid suspensions. In particular, we describe a distance dependent enhancement on silver island films (SIFs), release of self-quenching of fluorescence near silver particles, and the applications of fluorescence enhancement near metalized surfaces to bioassays. We discuss a number of methods for various shaped silver particle deposition on surfaces. 相似文献