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51.
P538 P204及其混合物从盐酸溶液中萃取Fe(Ⅲ)的平衡可分别表达为: P538: Fe~(3 ) 4/j(H_2A)j(o) K′_A Fe(HA)_3·H_2A(o) 3H~ P204: Fe~(3 ) 2H_2B_2(o) K′_B FeB_3·HB(o) 3H~ P538 P204:Fe~(3 ) 2/j(H_2A)j(o) H_2B_2(o) K′_(AB) Fe(HA)_2B·HB(o) 3H~ 其表观萃取平衡常数分别为 lgK_A=4.46±0.09 lgK_B=3.44±0.08 lgK_(AB)=5.47±0.10 等摩尔的P538,P204混合物有最大的协同萃取系数。 相似文献
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基于碳纳米管和铁氰酸镍纳米颗粒协同作用的葡萄糖生物传感器 总被引:8,自引:1,他引:8
将制备的铁氰酸镍纳米颗粒(NiNP)与多壁碳纳米管(CNT)混合, 分散于壳聚糖溶液中, 形成一种新的纳米复合成分(NiNP-CNT-CHIT), 将其修饰在玻碳电极表面. 新复合膜体现了NiNP和CNT之间的协同作用, 由于CNT的良好的传递电子性能, 促使NiNP催化氧化还原能力有了较大的提高. 此NiNP-CNT-CHIT复合膜修饰的玻碳电极在较低电位下对过氧化氢具有良好的电催化性能, 与NiNP-CHIT膜比较, 测定H2O2的灵敏度增大了50倍. 通过戊二醛在电极表面固定葡萄糖氧化酶制备了一种新的葡萄糖传感器. 该传感器在-0.2 V下对葡萄糖的线性范围为0.05~10 mmol/L, 检测下限为10 μmol/L. 相似文献
56.
Maria Atanassova Victoria Lachkova Nikolay Vassilev Sabi Varbanov Ivan Dukov 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):173-179
The synergistic solvent extraction of five selected lanthanoid ions (La3+, Nd3+, Eu3+, Ho3+ and Lu3+) with a 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone(HP) and the 5,11,17,23-tert-butyl-25,26,27,28-tetrakis(dimethylphosphinoylmethoxy)calix[4]arene, (S) in CHCl3 has been studied. It was found that in presence of this phosphorus-containing calix[4]arene the lanthanoids have been extracted
as LnP3 · S. On the basis of the experimental data, the values of the equilibrium constants have been calculated. The influence of
the synergistic agent on the extraction process has been discussed. A synergistic effect of almost three orders of magnitude
occurs in the extraction of Ln(III) with mixture of HP and S. The values of the separation factors (S.F.) between the adjacent
elements have been evaluated.
On the basis of the IR and NMR spectra the stoichiometry and the structure of the solid complexes of Eu(III) with HP and Eu(III)
with HP and S were proposed. 相似文献
57.
水热污泥与煤在混燃过程中的协同效应特性研究 总被引:1,自引:0,他引:1
水热污泥与煤在混燃过程中的协同效应特性研究 《燃料化学学报》2018,46(12):1437-1446
以城市污泥衍生的水热污泥(SS-derived hydrochar)为对象,结合傅里叶红外光谱分析(FT-IR)、X射线荧光光谱分析(XRF)和X射线衍射分析(XRD)等对比研究了水热污泥与三种不同品阶煤(褐煤、烟煤和无烟煤)在有机/无机结构与燃料特性上的异同;同时,通过热重(TG)与偏差分析(Deviation)考察水热污泥与各阶煤在不同混合比例条件下的协同燃烧行为及其作用机制。结果表明,污泥经过水热处理后其有机结构和燃烧行为均提升至与煤相似的水平,该过程不仅改善污泥的燃烧特性,并增强其与煤之间的协同燃烧效应。水热污泥中适量的轻质组分与(碱)碱土金属能在混合燃烧过程中加速煤的失重速率,其对三种煤的促进作用可达4.4%-16.1%(褐煤)、1.9%-9.4%(烟煤)和4.8%-12.1%(无烟煤)。总体而言,水热污泥与褐煤混合而成的燃料在燃料性能上具有较大的优势,并且其混合比例以30%(水热污泥):70%(褐煤)与50%(水热污泥):50%(褐煤)为宜。 相似文献
58.
Poly (vinyl alcohol) (PVA)–functionalized β-cyclodextrin (β-CD) polymer crosslinked by citric acid (PVA-g-CD) was synthesized, characterized and evaluated for the catalytic oxidation of cinnamaldehydes. The polymer showed good activity and selectivity to aldehydes for some structurally diverse cinnamaldehydes. The enhanced catalytic activity may be attributed to the synergistic effect of the intermolecular weak interactions between β-CD and the functional group of PVA. In addition, calcium peroxide as a solid oxidant was found to significantly affect the reaction. This catalyst can be recovered and reused for five times without a significant loss in its activity and selectivity. 相似文献
59.
Olanrewaju Owoyomi Grace Oluwafunmilayo Ogunlusi Omoetan Monday Olatan 《Physics and Chemistry of Liquids》2016,54(6):769-778
Effects of two anionic hydrotropes – sodium benzoate (NaBz) and sodium salicylate (NaSal) – on the mixed-micelle formation with an amino-acid-based surfactant – sodium lauroylsarcosinate (SLS) – in water were investigated by the conductometric method. Specific conductivity was measured for SLS/NaBz/water and SLS/NaSal/water systems to determine the critical micelle concentration (cmc). Using the regular solution theory for non-ideal mixing, the pairwise interaction parameter, β12, and micellar composition, χ, were estimated in the mixed micelle. The cmc values of the surfactant–hydrotropes mixtures were generally lower than those predicted from the ideal mixing theory. The β12 values are generally negative for the two systems at all mole fractions with an average value of ?2.83 for the SLS/NaBz and ?3.31 for SLS/NaSal systems, respectively, indicative of a strong attractive interaction between the SLS/NaBz and SLS/NaSal mixed micelle. The calculated thermodynamic parameters of micellisation all indicated spontaneity in mixed-micelle formation for the systems studied. 相似文献
60.
Effect of anion of polyoxometalate based organic–inorganic hybrid material on intumescent flame retardant polypropylene 下载免费PDF全文
In this work, 12‐tungestocobaltic acid based organic–inorganic hybrid material, [Bmim]6CoW12O40 (CoW) was synthesized and applied as a synergist in polypropylene (PP)/intumescent flame retardant (IFR) composites. The flame retardant properties were investigated by the limiting oxygen index (LOI), UL‐94 vertical burning test, thermal gravimetric analyzer (TGA), cone calorimeter and scanning electron microscopy (SEM) etc. The results showed that the PP composites with 16 wt% IFR and 1 wt% CoW achieves the UL‐94 V‐0 rating and gets a LOI value 28.0. However, only add no less than 25 wt% single IFR, can the PP composites obtain the UL‐94 V‐0 rating, which suggests that CoW has good synergistic effects on flame retardancy of PP/IFR composites. In addition, the SEM and cone calorimeter tests indicated the CoW improves the quality of char layer. The rate of char formation has been enhanced also because of the existence of CoW. It is the combination of a better char quality and a high rate of char formation promoted by CoW that results in the excellent flame retardancy of PP/IFR composites. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献