Fe-V-N稀合金中空位复合体特性的研究(Ⅱ)

本文利用离散变分法,集团模型和三维数值弛豫技术,研究了Fe-V-N稀合金中V-N-空位复合体的几何构型,正电子湮没特性和电子结构。根据正电子湮没寿命实验的结果和总能量极小原理,确定了V和N在V-N-空位复合体中的最佳占据位置。分析了V-N-空位复合体的成键特性和电荷转移情况。 关键词：     

核磁共振弛豫速率方法测定模拟正铁色素的结构

在生命体系内正铁色素具有摄铁和输铁的功能,人工合成的模拟化合物具备了正铁色素的主要功能基团和相近的性质.本工作利用铁(Ⅲ)离子的顺磁性质,测定不同铁(Ⅲ)离子浓度下模拟正铁色素的诱导弛豫时间,根据简化了的Solomon—B1oemoergen公式,计算出铁(Ⅲ)离子到所有被测质子(即氢原子)的相对距离,比较清楚地得到模拟正铁色素在溶液中的构象。     

三核铁甲酸簇合物[Fe_3(μ_3-O)(μ-O_2CH)_6(H_2O)_2(O_2CH)]·2H_2O在乙炔、水汽体系中的反应行为

本文研究了[Fe_3(μ_3-O)(μ-O_2CH)_6(H_2O)_2(O_2CH)]·2H_2O(简称)在乙炔、水汽体系中的反应行为。发现当温度高于220℃,脱落部分配体的具有活化乙炔进行加成反应的性能。采用原位红外光谱法和气相色谱法对此反应过程进行了跟踪探索,报道了产物的定性及半定量结果。     

Fe(Ⅲ)-磺基水杨酸褪色光度法测定物样品中的硫普罗宁

建立了Fe(Ⅲ)-磺基水杨酸褪色光度法测定硫普罗宁的新方法.结果表明,在酸性介质中,硫普罗宁分子中的巯基(—SH)可将Fe3+还原为Fe2+,采用磺基水杨酸作为Fe3+的显色剂,借褪色分光光度法间接测定了硫普罗宁含量.显色体系最大吸收波长为480nm,硫普罗宁在0.50-4.0μg/mL浓度范围内与AA呈良好的线性关系,线性回归方程为△A=0.0065+ 13C(μg/mL),线性相关系数r=0.9997,检出限为0.00016μg/mL.方法成功用于实际药品中硫普罗宁的含量测定.     

温度对Fe(Ⅲ)与牛血清白蛋白结合作用的影响

运用荧光光谱法研究了铁(Ⅲ,Fe3+)与牛血清白蛋白(Bovine Serum Albumin,BSA)的相互作用。在290K、308K时,随着Fe3+浓度的增大BSA发射峰略有蓝移,荧光强度降低,根据Stern-Volmer方程求出了Fe3+对牛血清白蛋白(BSA)荧光猝灭的常数,并探讨了BSA荧光猝灭机制,为静态猝灭,温度没有改变Fe3+对BSA的猝灭机制。根据公式lg(F0/F-1)=lgKA+nlg[C]求出了二者在两个温度时的结合常数(KA)以及结合位点数(n),经过数据分析后,得到了三个热力学参数吉布斯自由能变(ΔG)、焓变(ΔH)和熵变(ΔS),结果表明温度升高Fe3+与BSA的作用增强,二者之间的作用力主要为疏水作用。     

有机共沉淀-火焰原子吸收光谱法测定水样及奶茶粉中的微量铅

研究了用4-(2-吡啶偶氮)-间苯二酚(PAR)为沉淀剂,以Fe(Ⅲ)为载体离子的共沉淀体系快速共沉淀分离富集水样和奶茶粉中的铅,并用火焰原子吸收光谱(FAAS)方法测定。共沉淀过程受体系酸度、载体铁、沉淀剂PAR的用量及陈化时间的影响。结果显示,在pH为6.0的条件下,能够定量共沉淀试样中的铅。方法检出限为18.7μg.L-1,用于水样及奶茶粉的加标回收率为94.2%～98.3%,相对标准偏差为1.03%～2.24%,排除了基体干扰,结果较为满意。本法与传统的共沉淀方法比较,具有快速、简便、重现性好的优点。     

分光光度法同时测定铝(Ⅲ)和铁(Ⅱ)

以甲基百里酚蓝(MTB)为显色剂、CTMAB为增溶增敏剂,利用系数补偿和双峰双波长的两次分光光度法同时测定铝(Ⅲ)和铁(Ⅱ)的结果令人满意.     

Effect of Metallic Film in Diamond Growth from an Fe—Ni—C System at High Temperature and High Pressure

The metallic film surrounding a diamond single crystal,which plays an important role the diamond growth from and Fe-Ni-C system,has been successfully investigated by using transmission-electron microscopy(TEM),Raman layer(near diamond)of the film by TEM and Raman spectroscopy,but a parallel relationship exists between the(111) plane of γ-(Fe,Ni) and the (100) plane of (Fe2Ni)3C in this region.Compared with that of the film has an increase of 0.9V.According to the microstructures on the film obtained by the TEM.Raman spectra,and XPS,the catalytic mechanism of the film may be assumed as follows.In the surface layer of the film,iron and nickel atoms in the γ-(Fe,Ni) lattice can absorb carbon atoms in the (Fe,Ni)3C lattice and make them transform to an sp^3-like state.Then carbon atoms with the sp^3-like structure are separated from the (Fe,Ni)3C and stack on the growing diamond crystal.This study provides a direct evidence for the diamond growth from a metallic catlayst-graphite system under high temperature and high pressure.     

Formation Mechanism and Orderly Structures of an Iron Film System Deposited on Silicone Oil Surfaces

A new iron film system,deposited on silicone oil surfaces by vapour phase deposition method,has been fabricated and its formation mechanism as well as orderly structures has been studied,It is found that the formation mechanism of the films obeys a two-stage growth model,which is similar to that to the other metallic films on liquid substrates,Large and orderly structures are observed in the continuous iron films.The experiments show that the orderly spatial structures result from the local material gathering in these nearly free sustained films.