LaNi4Fe催化合成氨反应性能的研究

用冶金法、还原扩散法、共沉淀法制得了LaNiFe,并对其催化合成氨反应性能进行了研究。实验结果表明:还原扩散法,共沉淀法制得的LaNi_4Fe催化活性均比冶金法好。X—射线分析指出LaNi_4Fe在合成氨反应过程中变为Ni_4Fe和LaN。     

铁／锌催化剂的物相结构及其还原行为的穆斯堡尔谱研究

以Mossbauer谱为手段,研究了用于F-T合成的Fe/Zn催化剂的物相结构,并考察了组成及制备方法的影响,同时还对其还原、碳化行为进行了探讨.发现锌对铁的还原有抑制作用,它能够稳定二价铁不被进一步还原.研究还表明,我们所研制的Fe/Zn催化剂是一种高分散度的铁锌化合物,室温下具有超顺磁特性.     

活泼配盐[(μ-RE)(μ-E′)Fe_2(CO)_6][Et_3NH][E,E′=S,Se]的亲电反应研究——蝶状Fe_2SSe及Fe_2Se_2簇合物的合成及表征

本文由［（μｔＢｕＳ）（μＣＯ）Ｆｅ２（ＣＯ）６］［Ｅｔ３ＮＨ］和硒粉形成的［（μｔＢｕＳ）（μＳｅ）Ｆｅ２（ＣＯ）６］［Ｅｔ３ＮＨ］，分别与溴化苄，二碘甲烷及邻一、间一、对一双（溴甲基）苯反应，合成了蝶状Ｆｅ２ＳＳｅ单簇物（μｔＢｕＳ）（μＰｈＣＨ２Ｓｅ）Ｆｅ２（ＣＯ）６（３ａ）和双簇物［（μｔＢｕＳ）Ｆｅ２（ＣＯ）６］２（μＳｅＺＳｅμ）［Ｚ＝ＣＨ２，ｏ．ｍ．ｐ双（亚甲基）苯］（４ａｄ）。类似地，由［（μＰｈＳｅ）（μＣＯ）Ｆｅ２（ＣＯ）６］［Ｅｔ３ＮＨ］和硫粉或硒粉所形成的［（μＰｈＳｅ）（μＳ）Ｆｅ２（ＣＯ）６］［Ｅｔ３ＮＨ］或［（μＰｈＳｅ）（μＳｅ）Ｆｅ２（ＣＯ）６］［Ｅｔ３ＮＨ］分别与对一双（溴甲基）苯反应合成了蝶状Ｆｅ２ＳＳｅ和Ｆｅ２Ｓｅ２双簇物［（μＰｈＳｅ）Ｆｅ２（ＣＯ）６］２［μＳ（ｐＣＨ２Ｃ６Ｈ４ＣＨ２）Ｓμ］（５ａ）及［（μＰｈＳｅ）Ｆｅ２（ＣＯ）６］２［μＳｅ（ＰＣＨ２Ｃ６Ｈ４ＣＨ２）Ｓｅμ］（５ｂ）。所有产物均经元素分析、ＩＲ和１ＨＮＭＲ表征。     

C(2×2)S/Fe(001)吸附体系的SCF-Xa-MS研究

采用SCF-X_α-MS方法, 对于C(2×2)S/Fe(001)吸附体系, 选择Fe_5S和Fe_9S两种原子簇模型, 研究了该吸附体系的电子结构、吸附成键特征及其相互作用图象。结果表明, S吸附于Fe(001)单晶表面具有较强的定域性质, S原子与底物Fe原子之间的吸附相互作用主要表现为S(3p)-Fe(4s,3d)之间的轨道相互作用。通过对表面吸附键长的优化, 其结果与X.S.Zhang等的ARPEFS的实验结果一致。     

ToF‐SIMS studies of the oxidation of Fe by D2O vapour: comparison with XPS

The oxidation of iron (Fe) by water (D₂O) vapour at low pressures and room temperature was investigated using time‐of‐flight (ToF) SIMS. The results supported those found previously using XPS and the QUASES^? program in that a duplex oxide structure was found containing a thin outer surface hydroxide (Fe(OD)₂) layer over an inner oxide (FeO) layer. The extraordinary depth resolution of the ToF‐SIMS profiles assisted in identifying the two phases; this resolution was achieved by compensation for surface roughness. A substantial concentration of deuterium was found in the subsurface oxide layer. This observation confirmed previous assessments that the formation of FeO was from the reaction of Fe(OD)₂ with outward‐diffusing Fe, leaving deuterium as a reaction product. Copyright © 2005 John Wiley & Sons, Ltd.     

Fluorescence quenching of anthropogenic fulvic acids by Cu(II), Fe(III) and UO(2)(2+)

The quenching of the fluorescence of three anthropogenic fulvic acids (FA) provoked by Cu(II) (pH 6.0), Fe(III) (pH 4.0) and UO₂²⁺ (pH 3.5), was analyzed by a non-linear method and by Stern-Volmer plots. The FA samples were extracted from composted sewage sludges (csFA), composted municipal wastes (mwFA) and composted livestock wastes (lsFA). Synchronous-scan fluorescence (SyF) spectra were collected as a function of metal ion concentration. Spectral data were treated by a self-modeling mixture analysis method (SIMPLISMA) to detect the SyF spectral band with the strongest quenching and to calculate the corresponding quenching profile. The analysis of these profiles by a non-linear method allowed the estimation of conditional stability constants (K) and of the percentage of non-complexing fluorophores. The same quantitative information was obtained by the modified Stern-Volmer equation taking into account the existence of fluorophores that do not participate in the complexation. Good agreement was found between the results of the two procedures. The log K calculated by the non-linear method were (standard deviation in parenthesis): csFA, Cu(II), 4.22 (5); Fe(III), 5.0 (1); UO₂²⁺, 5.2 (2); mwFA, Cu(II), 4.21 (3); Fe(III), 5.6 (2); UO₂²⁺, 4.7 (3); lsFA, Cu(II), 4.51 (8); Fe(III), 5.5 (2); UO₂²⁺, 3.6 (2).     

废水中偏二甲肼在Ni/Fe催化剂上的催化分解研究

研究了Ni/Fe催化剂对废水中偏二甲肼臭氧化分解的催化作用,考察了组分含量、体系的pH值和偏二甲肼初始浓度对催化反应的影响.结果表明,Ni/Fe催化剂对水中偏二甲肼的臭氧化具有良好的催化活性.催化剂组分含量、体系的pH值和初始浓度对反应的影响程度不大.对催化剂的XRD表征结果表明,催化剂主要由尖晶石结构的铁酸盐和FeNi3合金相组成,催化剂的良好催化性能与催化剂中尖晶石结构的铁酸盐和FeNi3合金相的形成有关.     

簇合物[Fe（DMF）6][W2S6]的合成,结构和性能研究

以(NH_4)_2WS_4、FeCl_3和NaS_2CNC_5H_(10)为原料,合成出[Fe(DMF)_6][W_2S_6]簇合物,用X射线衍射法测定了晶胞结构.其晶胞参数为a=0.8778(1)nm,b=0.9467(3)nm,c=1.1362(6)nm,α=71.506(1)°,β=74.775(2)°,γ=74.775(2)°,ν=0.84806nm~3,Z=1.晶体结构经块矩阵最小二乘法精修后,最终偏离因子R=0.0811.此外还进行了红外光谱、紫外可见光谱的测定.     

用MES及XRD研究FT合成催化剂的活性结构

采用穆斯堡尔谱及Ｘ光衍射法研究了共沉淀法制备的不同Ｆｅ／Ｍｎ比催化剂在焙烧、合成气还原及ＦＴ反应后体系相结构的变化。结果表明：锰助剂的加入使催化本相由铁磁性逐渐转化为超顺磁性，相应使催化剂还原逐渐难，Ｍｎ助剂促进了ＦＴ合成反应进行。反应性能与Ｆｅ／Ｍｎ尖晶石（Ｆｅ１－ｙＭｎｙ）３Ｏ４组成含量及式中ｙ大小密切相关，与ＭｎＣｏ３及ＭｎＯ的存在也有一定关系。富铁催化剂中Ｍｎ主要起电子助剂作用，而富锰催化     

ICP-AES法测定锌阳极中的铝、镉、铁、铜、铅

通过分析高频功率、雾化压力、辅助气流量和泵速等试验条件，建立了ICP-AES法测定锌阳极中铝、镉、铁、铜、铅的方法。用该方法测定锌阳极中的铝、镉、铁、铜、铅，其RSD分别为0.17%、0.63%、2.7%、5.2%、2.5%，回收率分别为99.3%-101.2%，99.3%-100.3%、97.1%-102.2%、97.8%-102.9%。对锌阳极试样进行测定，该方法的测定结果与GB4951-85方法的测定结果基本一致。