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1.
迄今为止,Belousov-Zhabotinskii(B-Z)振荡反应中Br~-浓度~CBr~-的变化主要用Br~-选择电极跟踪监测,取得了一定的成果。但是有一些研究表明,由于受到体系中KBrO_3等物种的干扰,Br~-选择电极的信号在定性和定量上都不一定是Br~-行为的真实反映。Noyes  相似文献   

2.
Aniline is an anthropogenic organic compound widely used in polymer, rubber, pharmaceutical and dye industries but also used in biodegradability assays of chemical compounds as a positive biodegradation standard. By the two approaches, the rapid determination of aniline is necessary because of the high toxicity of aniline on hemoglobin. A high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) method for the determination of aniline in water is described here. This method, using benzylamine as internal standard, was validated. No time-consuming sample preparation was needed. A rapid separation (7 min between two chromatographic runs) of aniline and benzylamine was performed on a Hypercarb porous graphitic carbon column using a gradient of methanol and 100 mM formic acid. The obtained limits of detection and quantification were 10 and 1 ng/mL, respectively. The response for aniline was quadratic. We show that this problem could be circumvented by showing that the [calculated concentration = f(introduced concentration)] function was linear. The linearity range was 10-1000 ng/mL. An example of an application consisting of an aniline 42-day degradation kinetic in water was demonstrated.  相似文献   

3.
Poly(ethylene glycol) (PEG) was modified with aniline groups at both the end, and then PEG‐PANI rod‐coil block polymers have been synthesized by polymerization of the aniline with the aniline‐modified PEG. FTIR, NMR, and elemental analysis provided the chemical strucutre of the as‐prepared polymers. The achiral rod‐coil copolymer could form different superstructures by means of self‐assembly when adding diethyl ether into its THF solution and the length of PANI segments is a key factor to the superstructures. AFM measurements revealed that they form spring‐like helical superstructures from the short PANI‐containing copolymers while these form fibrous helical superstructures from the longer PANI‐containing copolymer. A possible mechanism of the helical superstructures is suggested in this article and the driving force is believed the π–π stacking of the rigid segment of the copolymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 12–20, 2008  相似文献   

4.
陈彤  付真金  祝良芳  胡常伟  田安民 《化学学报》2003,61(11):1701-1703
设计制备了Ni-Zr-Ce/Al_2O_3催化剂,研究了其上用H_2O_2直接将苯氧化胺化 合成苯胺的活性。发现在常压、50 ℃的温和条件下,该催化剂对苯、氨水与 H_2O_2直接氧化胺化生成苯胺有较好活性,并且其对苯胺的选择性远远大于对苯酚 的选择性。提高反应原料中氨水对苯的比例,能提高苯胺的收率,且不会增加苯酚 的生成量。本方法能耗低,原子利用率高,为苯胺的绿色合成提供了一条新的路径 。  相似文献   

5.
Chemically modified ordered mesoporous carbon CMK-3 materials were prepared by means of an easy wet-oxidative method in 2 mol/L nitric acid aqueous solution. A large amount of oxygen-containing functional groups were introduced onto the CMK-3 surface. Modified CMK-3(m-CMK-3) and aniline monomer were polymerized via an in situ chemical oxidative polymerization method. Morphological characterizations of m-CMK-3/PANI (polyaniline) composites were carried out via field emission scanning electron microscopy(SEM)...  相似文献   

6.
Functionalization of polyols with aromatic amines offers a potential route to modify properties of polyurethanes, polyamides, and epoxies. Additionally, aniline termination of polyether backbones provides the opportunity to speed up reactions with isocyanates relative to hydroxyl functionalization and slow down epoxy reactions compared to reactions with primary and secondary amines. In this article, the synthesis, characterization, and physical properties of aniline‐terminated polyols with varying molecular weight, monomer type, and functionality is described. Numerous analytical techniques are employed to track the chemical modification kinetics and the resulting aniline functionalized polyol properties. In addition, synthesis and properties of poly(urethane‐urea) elastomers from several of the modified polyols are presented. The effect of hard segment composition and process temperature on tensile properties, dynamic mechanical properties, phase morphology, and chemical resistance is explored. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1730–1742  相似文献   

7.
Aniline chemical oxidative polymerisation (COP), which produces various polyaniline (PANI) and oligoaniline supra-molecular structures, can be regarded as an in situ self-assembly process. This review provides a brief introduction to recent work on the structural characters and self-assembly behaviours of oligomeric aniline chemical oxidation products; it is focused on the relationships between the oligomeric species and morphology of the final products such as PANI nanoparticles, nanofibres/rods, nanotubes or oligoaniline nanosheets, micro/nanospheres in aniline COP systems. Several mechanisms proposed as explanations for the formation of typical supra-molecular structures are discussed in order to illustrate the roles of aniline oligomers. This article concludes with our perspectives on future work remaining to be done to uncover the formation mechanism of supra-molecular structures constructed by aniline chemical oxidation products and their controllable synthesis.  相似文献   

8.
Graphene oxide/copolyaniline (GO/NCOPA) composites were prepared with GO, which was prepared using a modified Hummers method and a monomer mixture containing aniline and ionic sodium diphenylamine sulfonate, where ionic N-substituted copolyaniline was synthesized by chemical oxidation. The GO/NCOPA composite, as a dry-base electrorheological (ER) fluid system, was dispersed in silicone oil. With the ionic substituent on the polymer chain, the composite showed both controllable electrical conductivity and higher polarization, which provide favorable factors for ER applications. The GO/NCOPA composite-based ER fluid containing a copolymer with an ionic group exhibited typical ER characteristics, as measured using a rotational rheometer equipped with a Couette-type cylinder and a high voltage generator. The dielectric spectra measure was correlated further with their ER performance.  相似文献   

9.
以猪血粉为原料,磷酸为活化剂,用化学活化法制备原位氮掺杂活性炭(BN-AC),并用于苯胺的吸附.采用元素分析、FTIR、XPS等分析方法研究了BN-AC的理化性质.分析结果表明BN-AC比表面积为461.0 m2·g-1,总孔容为0.3 cm3·g-1.BN-AC表面含有吡啶氮、吡咯氮和石墨氮,成功地保留了血粉中的N成...  相似文献   

10.
A high-throughput multiparameter optimization of chemical oxidative polymerization conditions has been developed for a facile synthesis of furan homopolymers and furan/aniline copolymers using a combinatorial method. The polymerization yield, molecular structure, and properties of the polymers would be optimized against typical polymerization parameters, including oxidant species, medium species, temperature, oxidant/monomer ratio, monomer concentration, dopant concentration, and furan/aniline comonomer ratio. The electrical conductivity, lead ion adsorptivity, chemical resistance, and thermal behavior of the polymers were also elaborated. It is found that only a combination of FeCl(3) and nitromethane as oxidant and medium, respectively, is appropriate for the furan homopolymerization. The homopolymerization yield increases consistently with an increase in the monomer concentration from 0.05 to 0.2 M and the FeCl(3)/furan molar ratio from 0.25 to 1.25. Although the as-prepared polyfuran exhibits very low conductivity, down to 10(-11) S cm(-1), the HCl- and HClO(4)-doped polyfurans possess much higher conductivities of 9.2 x 10(-8) and 2.38 x 10(-5) S cm(-1), respectively. In addition, the conductivity of the furan/aniline copolymer rises steadily with increasing aniline content, although the copolymerization yield shows a minimum at the furan/aniline molar ratio of 60/40, which is evidence of the occurrence of a real copolymerization between the furan and aniline monomers. The difficulty of synthesizing conducting polyfuran could be overcome to some extent by the polymerization in an appropriate condition optimized in this study. Particularly, the difficulty of synthesizing poly(furan-co-aniline) having much higher conductivity than the polyfuran would be largely conquered by chemical oxidative copolymerization of furan with aniline.  相似文献   

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