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31.
In this paper we report a simple methodology for obtaining (+) trans - 1,2 - epoxylimonene (1b) in high purity (>99% HRGC) and reasonable quantity. The mixture of 1a and 1b in CH2Cl2 is stirred with 1M NaHSO3 in water. Under these conditions 1a is completely destroyed, while 1b is only partially destroyed.  相似文献   
32.
Journal of Solid State Electrochemistry - Polyaniline was electrosynthesized using three voltammetric cycles on carbon fiber felts annealed at 1400, 1600, 2000, and 2300 K. Felts and...  相似文献   
33.
Journal of Sol-Gel Science and Technology - This study reports the development of a functional adsorbent synthesized by the molecular imprinting method in a sol–gel matrix. The adsorption...  相似文献   
34.
A thermally stable carbocationic covalent organic network (CON), named RIO-70 was prepared from pararosaniline hydrochloride, an inexpensive dye, and triformylphloroglucinol in solvothermal conditions. This nanoporous organic material has shown a specific surface area of 990 m2 g−1 and pore size of 10.3 Å. The material has CO2 uptake of 2.14 mmol g−1 (0.5 bar), 2.7 mmol g−1 (1 bar), and 6.8 mmol g−1 (20 bar), the latter corresponding to 3 CO2 molecules adsorbed per pore per sheet. It is shown to be a semiconductor, with electrical conductivity (σ) of 3.17×10−7 S cm−1, which increases to 5.26×10−4 S cm−1 upon exposure to I2 vapor. DFT calculations using periodic conditions support the findings.  相似文献   
35.
This review emphasizes the breadth of metallic and metallic-like polymers evaluated as to thermal properties. Techniques usefully applied to particular systems are noted with the aim of suggesting their application to other systems.  相似文献   
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Previous interpretations of the electron spin resonance spectrum of Wurster's Blue cation are shown to be incorrect. In particular the nitrogen hyperfine splitting constant previously quoted as 0·28 gauss is, in fact, 7·0 gauss. A complete analysis of the spectrum is described.  相似文献   
39.
Synthetic flow is proposed as a modifier agent of color firing in tile ceramic mass during the sinterization process, turning the red color firing into whiteness. Therefore, the 57Fe Mössbauer spectroscopy was used to understand how the interaction of the iron element in the mechanism of color firing mass occurs in this system. The results suggest that the change of color firing can be alternatively due to two main factors: (i) diluting the hematite content in the sample because of the use of synthetic flow and (ii) part of the hematite is converted in other uncolored crystal structures, which makes the final color firing lighter.  相似文献   
40.
As the addition of low concentrations of oxygen can favor the initial degradation of benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds, this work verified the applicability of the microaerobic technology to enhance BTEX removal in an anaerobic bioreactor supplemented with high and low co-substrate (ethanol) concentrations. Additionally, structural alterations on the bioreactor microbiota were assessed throughout the experiment. The bioreactor was fed with a synthetic BTEX-contaminated water (~ 3 mg L?1 of each compound) and operated at a hydraulic retention time of 48 h. The addition of low concentrations of oxygen (1.0 mL min?1 of atmospheric air at 27 °C and 1 atm) assured high removal efficiencies (> 80%) for all compounds under microaerobic conditions. In fact, the applicability of this technology showed to be viable to enhance BTEX removal from contaminated waters, especially concerning benzene (with a 30% removal increase), which is a very recalcitrant compound under anaerobic conditions. However, high concentrations of ethanol adversely affected BTEX removal, especially benzene, under anaerobic and microaerobic conditions. Finally, although bacterial community richness decreased at low concentrations of ethanol, in general, the bioreactor microbiota could deal with the different operational conditions and preserved its functionality during the whole experiment.  相似文献   
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