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41.
The electrochemical behavior of the gold electrode modified by hybrid bilayer membranes in different concentrations of Fe(CN)63?/Fe(CN)64? was investigated by electrochemical impedance spectroscopy and cyclic voltammetry technology. The electron transfer between gold and the redox species separated by the hybrid bilayers assembly was completed by an electron tunneling process. A detailed equivalent circuit for electron transport across the HBMs is proposed. It was found that the apparent effective thickness of the hybrid bilayer membranes was lower than that of the sum of the chain length of octadecanethiol and phospholipid so some possible collapsed sites might exist at the hybrid bilayer membranes.  相似文献   
42.
A widely and continuously tunable optical parametric generator (OPG) pumped by a 1064-nm acoustooptically Q-switched diode-end-pumped Nd:YAG laser based on MgO-doped periodically poled LiNbO3 crystal with a multigrating structure (29.2-30.4 μm) is reported.A broad continuous signal spectrum of 1513-1700 nm is obtained by changing the crystal grating periods from 29.2 to 30.4μm and by tuning the crystal temperature from 30 to 180 ℃ simultaneously.When the average pump power is 1.82 W with pulse duration of about 70 ns operating at a repetition rate of 10 kHz,the maximum signal output power of the periodically poled MgO-doped lithium niobate (PPMgLN) OPG is about 210 mW corresponding to the idler and total powers of 118.4 and 328.4 mW respectively.  相似文献   
43.
Fission properties of the actinide nuclei are deduced from theoretical analysis. We investigate potential energy surfaces and fission barriers and predict the fission fragment mass yields of actinide isotopes. The results are compared with experimental data where available. The calculations were performed in the macroscopic-microscopic approximation with the Lublin-Strasbourg Drop (LSD) for the macroscopic part, and the microscopic energy corrections were evaluated in the Yukawa-folded potential. The Fourier nuclear shape parametrization is used to describe the nuclear shape, including the non-axial degree of freedom. The fission fragment mass yields of the nuclei considered are evaluated within a 3D collective model using the Born-Oppenheimer approximation.  相似文献   
44.
A new approach to synthesis of thiosulfonates has been developed under mild conditions without any oxidants and promoting reagents through a Pd/ZrO2 nanocomposite photocatalyst catalyzed decomposition of sulfonyl hydrazides. This protocol gave the products in moderate yields, comparable to the best results reported so far. Finally, a plausible reaction mechanism was proposed.  相似文献   
45.
Magnetic nanoparticle-assisted solid-phase dispersion (MMSPD) combined with dispersive liquid–liquid microextraction (DLLME) prior to high performance liquid chromatography with fluorescence detector (HPLC–FLU) is presented for determination of ultra trace Bisphenol A (BPA) in water. Magnetic multi-walled carbon nanotubes (MMWCNTs) were synthesized for the adsorption of BPA in water. Ultra trace BPA in water was transferred into the elute solvent by the MMSPD and further concentrated into trace volume extraction solvent by the DLLME. The limit of detection and limit of quantitation were 0.003 and 0.01 µg L?1, respectively. Good linearity of BPA was found, ranging from 0.01 to 10 µg L?1, with good squared regression coefficient (R 2) of 0.9999. Additionally, relative recoveries were 83.1 and 95.9% for two environmental water samples spiked with 0.20 µg L?1 BPA, respectively. All results showed that the MMWCNTs nanoparticle-assisted MMSPD–DLLME–HPLC–FLU method was simple and reliable for the determination of ultra trace BPA in environmental water.  相似文献   
46.
The paper is concerned with the development of hybrid-Trefftz (HT) p-element for nonlinear analysis of Reissner-Mindlin plates resting on an elastic foundation. The foundation may be of Winkler-type or Pasternak-type. Exact solutions of the Lame-Navier equations are used for the in-plane intraelement displacement field and an incremental form of the basic equations is adopted. With the aid of incremental form of these equations, all nonlinear terms may be taken as pseudo-loads. Moreover, some modifications have been made on the nonlinear boundary equations to simplify the ensuing derivation. As a result, the in-plane and out-of-plane equations are uncoupled, and then the derivation for the HT finite element (FE) formulation becomes very simple. The practical efficiency of the new element model has been assessed through several examples.  相似文献   
47.
The oxidation of polysulfides to element sulfur in charge process was studied by solution thermodynamic analysis and means of cyclic voltammetry (CV), X-ray diffraction (XRD), and charge?Cdischarge test. Basing on the solution thermodynamic analysis, the oxidation process of polysulfides to element sulfur would arise only if the charge voltage exceeds 3.36 V in a lithium?Csulfur cell employing 1.0 M LiN(CF3SO2)2 in 1,2-dimethoxy ethane. Furthermore, the minimum of charge voltage which can push the oxidation would fall down with the increasing solubility of elemental sulfur in electrolyte solution. These analyses were confirmed by practical measurements. One new anodic peak corresponding to the oxidation process of polysulfides to solid sulfur was observed by CV. Both XRD patterns and charge?Cdischarge test showed that the element sulfur appeared in the cathode after the battery was charged over 3.4 V. Hence, the lithium?Csulfur cell charged over 3.4 V exhibited an improved cycle life since the capacity degradation between the first cycle and the second was depressed. In order to improve the energy efficiency, carbon disulfide was added in the electrolyte solution of lithium?Csulfur cell to increase the solubility of sulfur.  相似文献   
48.
Wang  Lujie  Wen  Xiaodong  Zhang  Xujun  Yuan  Shuntao  Xu  Qingbo  Fu  Feiya  Diao  Hongyan  Liu  Xiangdong 《Cellulose (London, England)》2021,28(9):5867-5879
Cellulose - In this article, carboxymethyl chitosan (CMC) and (3-carboxypropyl) trimethylammonium chloride (CPTC) were used as raw materials to prepare an antibacterial cotton fabric with excellent...  相似文献   
49.
The inclusion complexation behavior of the dye guest molecule neutral red with three kinds of water-soluble p-sulfonated calix[n]arene sodium (n=4,6,8) was investigated. p-Sulfonated calix[4,6,8]arene sodium (pSC4, pSC6, pSC8) can react with neutral red to form inclusion complexes, which were confirmed by UV-vis absorption and fluorescence spectroscopy. Fluorescence spectroscopy experiments were performed in pH=4.6 acetic buffer solutions at 25 °C to calculate the stability constants (K S) for the stoichiometric 1:1 inclusion complexes of pSC4, pSC6 and pSC8 with neutral red. The thermodynamic parameters for the inclusion complexes were determined through a van’t Hoff analysis. Formation of the inclusion complexes of pSC4, pSC6 and pSC8 with neutral red was driven by favorable enthalpic changes with their accompanying negative entropy changes. The complex stability constants monotonically increased with the number of phenolic units in the calixarene ring, which was attributed mainly to electrostatic interactions and hydrogen bonding, rather than to the cavity size.  相似文献   
50.
本文描述了为测量HL-1装置电子密度分布而研制的多道远红外(FIR)激光干涉仪系统及其特点。首次对装置在弹丸加料以及拉瓦尔(Laval)超声分子束注入实验条件下的等离子体电子密度时-空分布进行了观测和初步分析。同时,介绍一种处理密度相移信号的新方法。  相似文献   
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