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51.
Youqian Bai Mengyu Gan Wei Qiu Feifei Cheng Dandan Fu Zhitao Li Sha Li 《Polymer Science Series B》2014,56(3):377-383
The polyaniline-gold (PANI-AuNPs) fibrillar nanocomposites were prepared via a simple one-pot synthesis route in ethylene glycol (EG) medium. The morphology of PANI-AuNPs was characterized by transmission electron microscopy (TEM), and their electrochemical properties were studied by CV, TAF and EIS measurement using an electrochemical workstation. The results show that the morphology of nanocomposites can be controlled by changing the temperature. The diameter of PANI-AuNPs composite nanofiber reduce from about 80 to 30 nm, and the size of AuNP also reduce from about 20 to 4 nm, with the rise of synthesized temperature. When the synthesized temperature is 10°C, the distribution of AuNPs is the best, and the amount of AuNPs dispersed in PANI is the most, as well as the electrochemical performance of PANI-AuNPs is the most excellent. 相似文献
52.
Multi‐walled carbon nanotube modified dummy‐template magnetic molecularly imprinted microspheres as solid‐phase extraction material for the determination of polychlorinated biphenyls in fish 下载免费PDF全文
Ning Gan Xidong Chen Yuting Cao Tianhua Li Pan Zhan 《Journal of separation science》2014,37(13):1591-1600
Novel multi‐walled carbon nanotube modified dummy‐template molecularly imprinted microspheres (MWCNTs@DMMIPs) were successfully synthesized as adsorbents for six kinds of polychlorinated biphenyls (PCBs). MWCNTs@DMMIPs were prepared by a surface molecular imprinting technique. Core–shell Fe3O4@SiO2 nanoparticles were employed as magnetic support. 3,4‐Dichlorobenzene acetic acid was used as a dummy template instead of PCBs, methacrylic acid was used as functional monomer and ethylene glycol dimethacrylate was used as the cross‐linker. The resulting absorbent was characterized by various methods. The adsorbent was employed for extracting PCBs and exhibited good selectivity and high adsorption efficiency. Furthermore, it was reusable and capable of magnetic separation. Adsorption kinetics fit well with a pseudo‐second‐order kinetic equation and also exhibited a three‐stage intra‐particle diffusion model. The Freundlich model was used to describe the adsorption isotherms. The materials were successfully applied to the magnetic dispersive solid‐phase extraction of six kinds of PCBs followed by gas chromatography with mass spectrometry determination in fish samples, the limit of detection of six kinds of PCBs were 0.0028–0.0068 μg/L and spiked recoveries ranged between 73.41 and 114.21%. The prepared adsorbent was expected to be a new material for the removal and recovery of PCBs from contaminated foods. 相似文献
53.
采用密度泛函理论UB3LYP方法对Co+在三重态及五重态势能面上催化N2O与C2H6进行循环反应的两态反应机理进行了研究. 运用Harvery方法优化了两自旋态势能面5个最低能量交叉点(MECP),计算了MECP处自旋-轨道耦合作用. 采用Landau-Zener公式计算了自旋翻转处的系间窜越几率,各MECP处均可发生有效系间窜越. 通过应用Kozuch提出的能量跨度模型,Co+催化N2O与C2H6在298K下反应生成CH3CHO时有最大的TOF值3.35×10-21 s-1. 相似文献
54.
Fengying Guo Ruiqing Li Jijing Xu Lianchun Zou Shucai Gan 《Colloid and polymer science》2014,292(9):2173-2183
The Gd-, Tb-, and Ho-doped W-type hexagonal ferrite Ba0.85RE0.15Co2Fe16O27 was fabricated by a facile route of low-temperature sol–gel self-propagating combustion. Furthermore, a combination of dielectric loss phase polyaniline and magnetic loss phase Ba0.85RE0.15Co2Fe16O27 as the microwave absorber in a core-shell architecture has been synthesized. The effect of different lanthanide ions Gd, Tb, and Ho on their microstructure, static magnetic properties, electromagnetic properties, and microwave reflection loss have been systematically studied. Our results show that the Ho-doped ferrite has the low microstructure parameters (a, c, and V) and high saturation magnetization (Ms) attributed to its ionic radius and magnetic moment. Moreover, it was found that the Ho-doped composite exhibited excellent microwave absorbing property with a minimum reflection loss (RL) of about ?15.1 dB at 9.4 GHz. The reflection loss of composite increases up to almost triple upon the combination of polyaniline and doped ferrite. Such lightweight and highly effective absorbers via combining the organic and inorganic phase into a core-shell architecture are highly desirable for microwave absorber in various applications. Figure
The synthesis and properties of the PANI/REBF composites 相似文献
55.
为考查阻尼参数对空爆荷载等效静载动力系数的影响,理论推导了空爆荷载下结构等效单自由体系弹塑性位移解及延性比解,设计并计算了阻尼比0.000 1~0.1、延性比1~4的20种典型工况的动力系数,并与现行抗爆设计规范动力系数公式结果进行了对比。结果表明:阻尼比小于0.000 1时可基本代表无阻尼状态,阻尼比0.01的动力系数比无阻尼的最大降低幅度为2.08%,数值差异很小,因此阻尼比为0.01以内时,可忽略阻尼对动力系数的影响;阻尼比0.05的动力系数比无阻尼的降低幅度约9.92%,数值差异较大,认为阻尼比0.05以上时将具有明显的经济效益;现行设计规范动力系数更适用于柔性结构体系,运用于刚性结构抗爆设计时,计算误差较大,对阻尼比较小的结构设计更不利。 相似文献
56.
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58.
Xiao-Xiong Gan Dariusz Bugajewski 《Bulletin of the Brazilian Mathematical Society》2011,42(3):415-437
Several kinds of formal Laurent series have been introduced with some restrictions so far. This paper systematically sets
up a natural definition and structure of formal Laurent series without those restrictions, including introducing a multiplication
between formal Laurent series. This paper also provides some results on the algebraic structure of the space of formal Laurent
series, denoted by
\mathbbL\mathbb{L}. By means of the results of the generalized composition of formal power series, we define a composition of a Laurent series
with a formal power series and provide a necessary and sufficient condition for the existence of such compositions. The calculus
about formal Laurent series is also introduced. 相似文献
59.
By swapping entanglements of 3×3-dimensional Bell states, we propose a quantum secure direct communication scheme, whose advantage
is to own the high source capacity. In addition, another light point is that only one set of measuring basis is needed in
this scheme. 相似文献
60.
This paper presents a reconstruction of the three-dimensional velocity field of a turbulent vortex ring by means of Taylor’s
hypothesis. Stereoscopic PIV is used to acquire three velocity component information on a plane. The accuracy of the Taylor’s
hypothesis for this particular flow pattern is first discussed, and the three-dimensional velocity and vorticity information
are then presented. This study also introduces an azimuthally averaging method in order to give a mean structure in cylindrical
coordinates from a single realization and from which turbulent stresses and production can be estimated. The azimuthally averaged
quantities are then compared with the ensemble-averaged results from the previous planar (two-dimensional and stereoscopic)
PIV experiments. 相似文献