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951.
The stimuli‐responsive vesicles were prepared via electrochemical oxidation on the mixture solution of ferrocenylmethyl‐trimethylammonium iodide (FcMI) and sodium deoxycholate (NaDC). The vesicle structure and morphology are characterized respectively by transmission electron microscopy (TEM), dynamic light scattering (DLS) and atomic force microscopy (AFM). The vesicle shells can be clearly observed by TEM with the thickness ranging from several to several tens of nanometers and their outer diameters at the range of 50‐200 nm. The formation of vesicular structures is also supported via AFM measurements, and the ratio of the diameter and height of the nanospheres was estimated to be ca. 10, indicating the shell collapse. The obtained results are significant for the preparation of smart supramolecular aggregates. 相似文献
952.
953.
Minrong Xu Lin Cui Ruixia Han Shiyun Ai 《Journal of Solid State Electrochemistry》2012,16(7):2547-2554
A novel biosensor was fabricated based on hemoglobin (Hb) immobilized onto cuprous sulfide (Cu2S) nanorods/nafion nanocomposite film for the detection of polyphenols in the presence of hydrogen peroxide (H2O2). The nanostructured inorganic–organic hybrid material formed by Cu2S nanorods and nafion provided a biocompatible microenvironment for Hb and increased the sensitivity for polyphenols detection. The modified electrodes were characterized by electrochemical impedance spectroscopy and linear sweep voltammetry. Parameters such as pH, H2O2 concentration, and the applied potential were optimized. Under optimum conditions, the biosensor gave linear response ranges of 7.0–110, 0.6–10, and 8–100 μM for catechol, hydroquinone, and resorcin, with the detection limits of 0.5, 0.03, and 0.6 μM (S/N?=?3), respectively. The developed biosensor exhibited a short response time within only 8 s with good stability and reproducibility. Such a novel biosensor showed great promise for rapid, simple analysis of polyphenols contents in real samples. 相似文献
954.
Selective removal of nitrate by using a novel macroporous acrylic anion exchange resin 总被引:1,自引:0,他引:1
Sandra Mueller 《中国化学快报》2012,23(5):603-606
An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO42-/ NO3- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features. 相似文献
955.
为实现二极管激光器垂直阵列输出光束具有小发散角、高指向精度的特点,简述了快轴准直(FAC)微透镜的光束准直原理,分析了调节装置的精度要求及透镜选择等问题。通过光学成像方法实时监测二极管激光bar条的近场像和远场像,对FAC透镜分别进行粗调节和细调节,获得了20个bar条连续输出2 kW,垂直阵列二极管激光快轴准直光束远场发散角4.4 mrad,bar条间准直光束指向精度不大于±1.7 mrad的准直效果,并对监测精度进行了简要分析。对影响光束准直效果的因素进行了分析,指出了工艺优化的重点。 相似文献
956.
957.
Suppose β1 α1 ≥0,β2 α2 ≥ 0 and(k,j) ∈R2. In this paper, we mainly investigate the mapping properties of the operator T_αβf(x,y,z)=∫_Q~2f(x-t,y-s,z-t~ks~j)e~(-2πit-β1_s-β2)t~(-1-α1)s~(-1-α2)dtds on modulation spaces, where Q~2 = [0,1] x [0,1] is the unit square in two dimensions. 相似文献
958.
959.
960.
α型硅钼蓝法测铝中硅的研讨 总被引:2,自引:0,他引:2
实验考察了影响硅钼蓝法结果重现性及准确性的因素;比较了α型硅钼蓝及β型硅钼蓝的异同、特点;提出了利用α型硅钼蓝法线性范围宽、稳定性好的优点,同时测定铸铝中高含量硅和铝合金中低含量硅的分析方法。 相似文献