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91.
The solid–liquid equilibria of the ternary system H2O–Fe(NO3)3–Co(NO3)2 were studied by using a synthetic method based on conductivity measurements.
Two isotherms were established at 0 and 15 °C, and the stable solid phases which appear are the iron nitrate nonahydrate (Fe(NO3)3·9H2O), the iron nitrate hexahydrate (Fe(NO3)3·6H2O), the cobalt nitrate hexahydrate (Co(NO3)2·6H2O) and the cobalt nitrate trihydrate (Co(NO3)2·3H2O). 相似文献
92.
Noor-ul H. Khan Santosh Agrawal Rukhsana I. Kureshy Sayed H.R. Abdi Surendra Singh Raksh V. Jasra 《Journal of organometallic chemistry》2007,692(20):4361-4366
An efficient method for the addition of trimethylsilyl cyanide (TMSCN) to various aldehydes and ketones has been described using Fe(Cp)2PF6 (2.5 mol%) as a catalyst under solvent free condition. Excellent yields of trimethylsilylether of cyanohydrin up to (94%) was achieved within 10 min. 相似文献
93.
向列相液晶被广泛应用于液晶显示中,但是由于杂质的存在,会导致液晶的驱动电压变大,增加能耗。 为了降低阈值电压和饱和电压,通常向液晶中添加纳米颗粒来提高电光性能。 本文利用水热法制备了表面粗糙和光滑的两种立方体Fe2O3纳米颗粒,其形貌均匀,尺寸约550 nm。 将二者分别掺杂到向列相液晶E7中,结果表明,粗糙立方体Fe2O3/E7复合体系具有比光滑立方体Fe2O3/E7复合体系和向列相液晶E7更优的电光性能,且在掺杂质量分数为0.4%时,其电光性能达到最优,阈值电压和饱和电压分别降低9.9%和11.6%,对比度增大80%,响应时间降低至6.0 ms。 这归因于粗糙立方体Fe2O3具有足够的表面积和表面所带电荷更多,所以会更易吸附体系中的杂质离子和减弱杂质离子的屏蔽作用,从而提高了电光性能。 相似文献
94.
95.
A new PVC membrane potentiometric sensor that is highly selective to Fe(III) ions was prepared by using 2-[(2-hydroxy-1-propenyl-buta-1,3-dienylimino)-methyl]-4-p-tolylazo-phenol [HPDTP] as a suitable carrier. The electrode exhibits a linear response for iron(III) ions over a wide concentration range (3.5 × 10−6 to 4.0 × 10−2) with a super Nernstian slope of 28.5 (±0.5) per decade. The electrode can be used in the pH range from 4.5 to 6.5. The proposed sensor shows fairly a good discriminating ability towards Fe3+ ion in comparison to some hard and soft metals such as Fe2+, Cd2+, Cu2+, Al3+ and Ca2+. It has a response time of <15 s and can be used for at least 2 months without any measurable divergence in response characteristics. The electrode was used in the direct determination of Fe3+ in aqueous samples and as an indicator electrode in potentiometric titration of Fe(III) ions. 相似文献
96.
The alkali sodium ferrate (IV) Na4FeO4 has been prepared by solid-state reaction of sodium peroxide Na2O2 and wustite Fe1−xO, in a molar ratio Na/Fe=4, at 400°C under vacuum. Powder X-ray and neutron diffraction studies indicate that Na4FeO4 crystallizes in the triclinic system P−1 with the cell parameters= a=8.4810(2) Å, b=5.7688(1) Å, c=6.5622(1) Å, α=124.662(2)°, β=98.848(2)°, γ=101.761(2)° and Z=2. Na4FeO4 is isotypic with the other known phases Na4MO4 (M=Ti, Cr, Mn, Co and Ge, Sn, Pb). The solid solution Na4FexCo1−xO4 exists for x=0-1 and we have followed the evolution of the cell parameters with x to determine the lattice parameters of the triclinic cell of Na4FeO4. A three-dimensional network of isolated FeO4 tetrahedra connected by Na atoms characterizes the structure. This compound is antiferromagnetic below TN=16 K. At 2 K the magnetic cell is twice the nuclear cell and the magnetic structure is collinear (μFe=3.36(12) μB at 2 K). This black compound is highly hygroscopic. In water or on contact with the atmospheric moisture it is disproportionated in Fe3+ and Fe6+. The Mössbauer spectra of Na4FeO4 are fitted with one doublet (δ=− 0.22 mm/s, Δ=0.41 mm/s at 295 K) in the paramagnetic state and with a sextet at 8K. These parameters characterize Fe4+ high-spin in tetrahedral FeO4 coordination. 相似文献
97.
Petrović A. F. Petrović D. M. Leovac V. M. Budimir M. 《Journal of Thermal Analysis and Calorimetry》1999,58(3):589-596
The paper describes the results of differential thermal analysis of the octahedral Fe(III) complexes of the general formula [Fe(HLn)2]Cl and Fe(HL3)L3, as well as of the corresponding ligands H2Ln (H2Ln — tridentate salicylaldehyde semi thiosemi- and S-methylisothiosemi-carabazones with n=1, 2 and 3 respectively). The decomposition of the complexes involving sulphur-containing ligands (H2L2 and H2L3) starts with sulphur elimination. In case of the complexes [Fe(HL2)]Cl and [Fe(HL3)]Cl sulphur evolves independently, whereas with Fe(HL3)L3 it is eliminated within the SCH3 group. In the former case, sulphur elimination takes place at the same temperature for both complexes. The change in the coordination mode, being a consequence of the replacement of O by S, has no essential effect on thermal stability of the coordination polyhedron. The complexes involving ONN coordination, realized with the H2L3 ligand, exhibit a comparatively highest thermal stability of the coordination polyhedron.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
98.
Fe3+/V5+/TiO2复合纳米微粒光催化性能的研究 总被引:29,自引:1,他引:29
采用溶胶凝胶法制备了Fe^3 /V^5 /TiO2复合纳米微粒作为光催化剂。光降解反应结果表明,其掺杂催化剂Fe^3 /V^5 /TiO2的光催化活性明显提高。光电化学研究显示,铁离子可以成为电荷陷阱,促进空穴的界面传递反应。适量钒离子掺杂使TiO2电极的光电流升高,导带中电子浓度的增大,加快了界面的电子传递反应。共掺杂催化剂中,Fe^3 、V^5 分别提供了空穴与电子的陷阱,同时加快了电子与空穴的界面传递反应,从 更有效地提高光催化活性。双组份共掺杂为提高TiO2光催化活性提供新的途径。 相似文献
99.
100.
Fe—Silicalite—2催化剂表面CO2加氢反应性能的研究 总被引:3,自引:0,他引:3
研究了Fe/Silicalite-2催化剂CO2加氢低碳烯烃反应性能,利用CO2-TPD,CO2/H2-TPSR和CO/H2-TPSR表征手段,考察了铁含量及MnO助剂对Fe/Silicalite-2催化剂CO2吸附脱附及加氢反应性能的影响,表明随铁含量增加可提高催化剂对CO2的吸附能力,有利于提高CO2加氢反应的转化率。 相似文献