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11.
The photocatalytic reduction of nitrogen monoxide (NO) with ethane on the hollandite type catalyst (K2Ga2Sn6O16KGSO) was investigated. Using a closed-gas circulating system equipped with a Q-MASS detector and in-situ diffuse reflectance FT-IR spectroscopy. The reactant gases of NO and 13C2H6 decreased with the increasing irradiation time. In contrast, the N2 yield increased proportionally to the conversion of 13C2H6. Nitrogen oxides such as N2O did not reach their detectable levels. The NO adsorbed on KGSO was found to change to its activated species by UV irradiation. The oxidized products of C2H6 such as CH3CHO increased in proportion to the reaction time. The present results strongly suggest that KGSO has remarkable photocatalytic activity for the reduction of NO with C2H6.  相似文献   
12.
乔庆龙  周伟  陈婕  刘文娟  苗露  尹文婷  徐兆超 《色谱》2019,37(8):872-877
为将生物体内微观的蛋白行为可视化并以宏观信号呈现出来对蛋白进行实时、动态分析,借助SNAP-tag蛋白标签技术与有机小分子荧光染料,构建了一系列用于活细胞内实时监测目标蛋白的免洗荧光探针。标签蛋白SNAP-tag能够特异性识别探针中的苄基鸟嘌呤,从而使目标蛋白共价连接上荧光团(萘酰亚胺),携带上荧光信使。此外,由于萘酰亚胺从水环境中被牵引至SNAP-tag蛋白的疏水空腔,其荧光信号呈现出2~13倍的增强。通过SNAP-tag标签蛋白与目标蛋白的融合,该荧光探针实现了对活细胞内线粒体蛋白CoX8A及核内蛋白H2B特异性识别,在免洗条件下完成了对目标蛋白的实时追踪及原位分析。  相似文献   
13.
刘宇  林祥钦 《应用化学》1998,15(2):44-47
用循环伏安与现场可见紫外光谱电化学方法研究了氯化4-特丁基苯氧基铁酞菁[(TbPc)Fe(Ⅲ)Cl]电化学行为.结果表明,在四氢呋喃溶剂中其正电位区经历了两步氧化过程,对应于Fe(Ⅲ)/Fe(Ⅳ)以及Fe(Ⅳ)/阳离子自由基的生成反应,负电位区还原过程经历了Fe(Ⅲ)/Fe(Ⅱ),Fe(Ⅱ)/Fe(Ⅰ)和Fe(Ⅰ)/阴离子自由基生成的3个步骤,阐述了配位效应对氧化还原机理的影响.指出Fe(Ⅳ)不寻常价态的出现,是阴离子Cl-的轴向配位对超常价态起到稳定作用的结果.  相似文献   
14.
磺化聚苯乙烯/聚吡咯复合膜   总被引:1,自引:0,他引:1  
磺化聚苯乙烯(SPS)/聚吡咯(PPy)复合膜是通过毗咯单体在SPS基体中原位聚合方法制成的.用FTIR研究SPS/PPy复合膜分子间的相互作用,特别是SPS中SO3阴离子在1200cm-1不对称伸缩振动港带的分裂,说明了聚吡咯是以阳离子的形式作用于SPS中SO3阴离子上,产生强的离子-离子相互作用.同时还研究了在复合过程中,引起SPS基体的微区结构与性能的变化.SPS由于吡咯单体的胀入和聚合,导致了SPS微相分离,复合膜在动态力学性能测试中出现了两个Tg转变,分别在124和145℃.  相似文献   
15.
Alternating copolymers of vinyl acetate (VAc) and maleic anhydride (MA) are produced preferentially when VAc and MA are copolymerized at moderate temperatures while random copolymers are produced at temperatures above 90°C. A charge-transfer complex (CTC) of VAc/MA exists at moderate temperatures but does not exist at temperatures above 90°C.  相似文献   
16.
The polyhydroxyurethane/attapulgite nanocomposites (PHU/ATP) were prepared by in-situ surface-initiated polymerization of a five-membered cyclic carbonate, 2, 2-bis [p-(1, 3-dioxolan-2-one-4-yl-methoxy) phenyl] propane (B5CC) and hexamethylene diamine, from the surface of the aminopropyl attapulgite nanoparticles (APATP) for the first time. The chemical grafting of the polymer on the surface of ATP was confirmed by FTIR and the morphology of the attapulgite nanoparticles in the nanocomposites was examined by TEM. The thermal stabilities of the polyhydroxyurethane (PHU) and the polyhydroxyurethane/attapulgite nanocomposites (PHU/ATP) were compared with thermogravimetric analysis (TGA).The %G of the attapulgite nanoparticles was also calculated from the results of TGA after the free polyhydroxyurethane was washed off.  相似文献   
17.
A long-chain surfactant, enzoylbenzyl-N,N-dimethyl-N-octadecylammonium bromide (BDOB) with a benzophenone group, was synthesized to modify the montmorillonites (MMT) for the preparation of nanocomposites via photo-induced polymerization. The BDOB-modified MMT was characterized by the fourier transform infrared spectrometer (FTIR), thermal gravimetric analyzer (TGA) and X-ray diffraction (XRD), and the results of XRD indicated that the intercalated structures of BDOB-modified MMT was obtained. The conversion of the bisphenol A epoxy diacrylate (EA) was quantified by the FTIR, and the results indicated that conversion increased with an increase in the amount of BDOB-modified MMT. The morphologies of the UV-cured EA/MMT nanocomposites prepared from this organically modified MMT were studied by means of XRD and TEM, and the results showed that all the samples contained an intercalated structure with partial exfoliated structure. The results of TGA and mechanical properties also indicated that the thermal and mechanical properties of UV-cured nanocomposites were significantly enhanced due to the presence of the long chain surfactant organically modified MMT.  相似文献   
18.
重度原油注空气低温氧化过程研究(英文)   总被引:1,自引:0,他引:1  
低温氧化反应对现场燃烧(ISC)技术点火的成功有十分重要的影响.采用高压氧化管,研究了不同温度压力下,新疆克拉玛依重度原油的低温氧化过程.结果表明,温度和压力的变化对低温氧化反应的放热程度、持续时间以及气体产物有明显影响.适合油样低温氧化反应的温度和压力分别为150℃和10MPa.此外,采用纯组分替代原油族组分进行低温氧化实验,研究低温氧化反应对原油族组分(饱和烃、芳香烃、胶质、沥青质)含量的影响.结果表明,原油所含族组分中,芳香烃组分最易被氧化,其含量由氧化前的19.17%减少到12.38%(150℃)和9.51%(250℃).随着低温氧化过程的进行,结构复杂的族组分(胶质、沥青质)的含量明显增加.实验数据对油藏实施注空气技术,以及该技术现场实施条件的确定有十分重要的指导意义.  相似文献   
19.
通过热分解法制备Cu模型催化剂,然后经浸渍制备ZrO2/Cu催化剂,采用SEM、XPS考察了催化剂表面形态和组成,并采用in-situ Raman考察了催化剂在还原和吸附CO和水的过程中随时间的变化。结果表明,还原前Cu催化剂表面主要存在CuO物种,而在ZrO2/Cu表面,除了CuO物种,还存在着大量的表面羟基物种。ZrO2/Cu相对Cu更加容易还原为Cu0,同时,ZrO2在催化剂表面聚集形成絮状态,而Cu催化剂还原后主要形成Cu2O物种。Cu催化剂表面吸附CO后,除了形成Cu-CO外,Cu2O物种均会迅速消失形成CO2。Cu催化剂对水的作用比较弱,但是ZrO2/Cu催化剂和水作用较强,并且通过Cu-OH中间物形成Cu2O物种。  相似文献   
20.
Antimony is an element of significant environmental concern, yet has been neglected relative to other heavy metals in electroanalysis. As such very little research has been reported on the electroanalytical determination of antimony at unmodified carbon electrodes. In this paper we report the electrochemical determination of Sb(III) in HCl solutions using unmodified carbon substrates, with focus on non-classical carbon materials namely edge plane pyrolytic graphite (EPPG), boron doped diamond (BDD) and screen-printed electrodes (SPE). Using differential pulse anodic stripping voltammetry, EPPG was found to give a considerably greater response towards antimony than other unmodified carbon electrodes, allowing highly linear ranges in nanomolar concentrations and a detection limit of 3.9?nM in 0.25?M HCl. Furthermore, the sensitivity of the response from EPPG was 100 times greater than for glassy carbon (GC). Unmodified GC gave a comparable response to previous results using the bare substrate, and BDD gave an improved, yet still very high limit of detection of 320?nM compared to previous analysis using an iridium oxide modified BDD electrode. SPEs gave a very poor response to antimony, even at high concentrations, observing no linearity from standard additions, as well as a major interference from the ink intrinsic to the working electrode carbon material. Owing to its superior performance relative to other carbon electrodes, the EPPG electrode was subjected to further analytical testing with antimony. The response of the electrode for a 40?nM concentration of Sb(III) was reproducible with a mean peak current of 1.07?µA and variation of 8.4% (n?=?8). The effect of metals copper, bismuth and arsenic were investigated at the electrode, as they are common interferences for stripping analysis of antimony.  相似文献   
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