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991.
Contribution of UV light to the decomposition of toluene in dielectric barrier discharge plasma/photocatalysis system 总被引:1,自引:0,他引:1
Hai Bao Huang Dai Qi Ye Ming Li Fu Fa Da Feng 《Plasma Chemistry and Plasma Processing》2007,27(5):577-588
The contribution of UV light from plasma and an external UV lamp to the decomposition of toluene in a dielectric barrier discharge
(DBD) plasma/UV system, as well as in a plasma/photocatalysis system was investigated. It was found that UV light from the
DBD reactor was very weak. Its contribution to the removal of toluene in the plasma/photocatalysis system could be ignored.
Whereas, the introduction of external UV light to the plasma significantly improves the removal efficiency of toluene by 20%.
The removal efficiency of toluene in the plasma/photocatalysis system increased about 22% and 16% when compared with a plasma
only system and plasma driven photocatalyst system, respectively. The increased toluene removal efficiency was mostly attributed
to the contribution of the synergy between plasma and UV light, but not to the synergy between plasma and photocatalysis.
The synergetic effect between plasma and photocatalysis was not significant. 相似文献
992.
通过X射线衍射及磁测量手段研究了Dy2AlFe16-xMnx化合物的结构和磁性.研究结果表明Dy2AlFe16-xMnx化合物具有六角相的Th2Ni17型结构.对x=1,2的样品采用X射线热膨胀测定法在104-647K的温度范围内测量了其热膨胀性质,发现这些化合物在低温下存在热膨胀反常现象,在居里点附近出现负膨胀性质.对自发磁致伸缩的研究结果表明Dy2AlFe16-xMnx化合物中存在着较强的各向异性的自发磁致伸缩,随着Mn含量的增加,其低温下的自发体磁致伸缩减弱.磁测量结果表明Mn的替代导致Dy2AlFe16-xMnx化合物的居里温度及自发磁化强度急剧下降. 相似文献
993.
采用sol-gel法制备了Zn2 掺杂的锐钛矿相纳米TiO2薄膜电极.通过光电流作用谱和电流-电位(I-U)曲线研究了掺杂不同浓度Zn2 的TiO2薄膜电极的光电特性.由光电流作用谱可知,Zn2 的掺杂可显著影响薄膜电极的光电流大小,且掺杂的最佳浓度与薄膜晶粒尺度有关.在320nm单色光照射下,掺杂浓度(摩尔浓度)为0.1%的薄膜电极光电流最大,与未掺杂的本征薄膜电极相比增幅达40%.I-U曲线表明,光照下,随电极电位由正到负逐渐降低,不同掺杂浓度的TiO2薄膜电极中均出现了阳极电流向阴极电流转换的现象,且Zn2 掺杂浓度可影响电极阳极电流的初始电位.另外,无光照的暗态下,各薄膜在负电位区域观察到了相似的随电位降低而迅速增大的阴极暗电流. 相似文献
994.
用射频磁控溅射结合传统退火的方法制备LiCo0.8M0.2O2 (M=Ni,Zr)阴极薄膜.X射线衍射、拉曼光谱、扫描电子显微镜等手段表征了不同掺杂的LiCo0.8M0.2O2薄膜.结果显示,700℃退火的LiCo0.8M0.2O2薄膜具有类似α-NaFeO2的层状结构.通过对不同掺杂锂钴氧阴极的全固态薄膜锂电池Li/LiPON/LiCo0.8M0.2O2的电化学性能研究表明,电化学活性元素Ni的掺杂使全固态电池具有更大的放电容量(56μAh/cm2μm),而非电化学活性元素Zr的掺杂使全固态电池具有更好的循环稳定性. 相似文献
995.
Fei Yu Roger Ruan Xiangyang Lin Yuhuan Liu Rong Fu Yuhong Li Paul Chen Yinyu Gao 《Applied biochemistry and biotechnology》2006,130(1-3):563-573
The purpose of this research was to study the kinetics of liquefaction of crop residues. The liquefaction of corn stover in
the presence of ethylene glycol and ethylene carbonate using sulfuric acid as a catalyst was studied. It was found that the
liquefaction yield was a function of ratio of solvent to corn stover, temperature, residence time, and amount of catalyst.
Liquefaction of corn stover was conducted over a range of conditions encompassing residence times of 0–2.5 h, temperatures
of 150–170°C, sulfuric acid concentrations of 2–4% (w/w), and liquefaction reagent/corn stover ratio of 1–3. The liquefaction
rate constants for individual sets of conditions were examined using a first-order reaction model. Rate constant increased
with the increasing of liquefaction temperature, catalyst content, and liquefaction reagent/corn stover ratio. Reuse of liquefied
biomass as liquefying agent was also evaluated. When using recycled liquefied biomass instead of fresh liquefaction reagent,
the conversion is reduced. It appeared that 82% of liquefaction yield was achieved after two times of reuse. 相似文献
996.
The microphase adsorption ‐ spectral correction (MPASC) technique has been described and applied to the aggregation of trypan blue (TB) in proteins. The formation of the microelectrostatic field in protein causes the Langmuir monolayer aggregation of TB. The adsorption ratio of TB to bovine serum albumin (BSA), ovalbumin (OVA), hemoglobin (Hb) and human γ‐globulin (γ‐G) was determined to be 14.8, 8.4, 2.8 and 27.6, respectively, and the adsorption constant of the aggregates to be 7.17 × 105, 4.88 × 106, 4.85 × 106 and 2.99 × 106. The adsorption ratio of TB to proteins interestingly indicates almost no relation to the array sequence of amino acid residues. The interaction of TB with proteins is sensitive at pH 3.29, and the reaction was applied to the determination of protein trace with satisfactory results. 相似文献
997.
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