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1.
1,3,5,7-四羧甲酯基二环[3·3·1] 壬-2,6-二烯-2,6-二醇(TMBN)与铁(Ⅲ)能形成稳定的红色配合物,其最大吸收波长在486nm 处,表观摩尔吸光系数为0. 26×10~4。本文研究了 TMBN 与铁(Ⅲ)的显色反应条件及共存干扰离子影响。测定了锌铝合金标样中微量铁的含量,获得较满意的效果。该试剂作为分光光度法测定铁的显色剂,文献尚未见报道。1,3,5,7-四羧甲酯基二环[3·3·1] 壬-2,6-二烯-2,6-二醇  相似文献   

2.
本文研究了2-[(3,5-diCl-2-吡啶)偶氮]-5-二乙氨苯酚(简称3,5-diCl-DEPAP)在非离子表面活性剂 OP 存在下,与铁(Ⅱ)显色反应的适宜条件,确定了配合物的组成.实验表明:在 pH=4~7范围内铁(Ⅱ)与3,5-diCl-DEPAP 形成1:2的紫红色配合物,试剂的最大吸收峰位于450nm 处,配合物的最大吸收峰位于570nm 处.ε=6.7×10~41·mol~(-1)·cm~(-1),遵守比耳定律的范围为0~10μg/25mL.  相似文献   

3.
研究了菲咯嗪与铁的显色反应,铁(Ⅱ)—菲咯嗪配合物的最大吸收波长为562nm,摩尔吸光系数为2.9×10~4L·mol~(-1)·cm~(-1)。本方法简便、快速,具有良好的选择性,用于营养品中微量铁的测定,结果准确。  相似文献   

4.
合成了氯化铽与L-酪氨酸和甘氨酸的三元固态配合物,用溶解-反应量热法测定了配位反应的反应物与产物的溶解焓。通过设计一个热化学循环,计算出了配合物的标准摩尔生成焓△fHm0[Tb(Tyr)(Gly)3Cl3·3H2O,s,298.15K]=-4290.57 kJ·mol-1。  相似文献   

5.
应用具有恒温环境的反应量热计,分别测定了[GdCl3·6H2O(s)+3Gly(s)](Gly代表甘氨酸)和配合物Gd(Gly)3Cl3·3H2O(s)在2mol·L-1HCl溶液中的溶解焓.根据盖斯定律设计一个热化学循环,可计算得到六水氯化钆和甘氨酸配位反应的反应焓ΔrHmθ(298.15K)=-9.471kJ·mol-1,并估算出配合物Gd(Gly)3Cl3·3H2O(s)在298.15K时的标准生成焓ΔfHmθ(298.15K)=-3629.67kJ·mol-1.  相似文献   

6.
合成了高氯酸镧和甘氨酸、丙氨酸的混配型配合物.经化学分析、热重、差热、及与有关文献对比,确定其组成为{La2(Gly)5(Ala)3(ClO4)6·2H2O}n,纯度为98.85%.用溶解量热法在具有恒定温度的反应热量计上分别测定了298.15K时反应物和产物在2mol·L-1的HCl中的溶解焓.设计一热化学循环求出配位反应的焓变△rHm,进而计算出配合物的标准生成焓:ΔfHm (La2(Gly)5(Ala)3(ClO4)6·2H2O)=-7146.92kJ·mol-1.  相似文献   

7.
量热法测定氯化镱与甘氨酸配合物的标准生成焓   总被引:2,自引:2,他引:0  
应用具恒温环境的反应热量计 ,分别测定了 [Yb Cl3· 6H2 O(s) +3 Gly(s) (Gly代表甘氨酸 ) ]和配合物 Yb(Gly) 3Cl3· 3 H2 O(s)在 2 mol· L- 1 HCl溶液中的溶解焓 .通过盖斯定律所设计的一个热化学循环 ,可计算得到六水氯化镱与甘氨酸配位反应的反应焓Δr Hmθ(2 98.1 5 K) =1 .0 73 k J· mol- 1 ,并估算出配合物 Yb(Gly) 3Cl3· 3 H2 O的标准生成焓Δf Hmθ(2 98.1 5 K) =-3 5 99.1 3 k J· mol- 1 .  相似文献   

8.
目的研究三元配合物La(Et2dtc)3(phen)的热化学性质.方法采用了微量热法和燃烧法.结果铜试剂(NaEt2dtc·3H2O)和邻菲咯啉(phen·H2O)与水合氯化镧(LaCl3·3.94H2O)在无水乙醇中反应,制得三元固态配合物La(Et2dtc)3(phen).在298.15 K下测得了该配合物的液相生成反应的焓变△rHθm(l),为(-8.801±0.043)kJ/mol,计算了固相生成反应的焓变△rHθm(s),为(70.428±0.293)kJ/mol;配合物的恒容燃烧能△cU为(-17 455.98±7.98)kJ/mol,其标准燃烧焓△cHθm和标准生成焓△fHθm经计算分别为(-17 475.19±7.98)kJ/mol,(-1 257.78±8.84)kJ/mol.结论IR光谱表明该配合物中La3+与3个NaEt2dtc中的6个硫原子双齿配位,同时与邻菲咯啉中的2个氮原子双齿配位,配位数为8.  相似文献   

9.
FeCl3和Fe2Cl6与KCl反应的热力学研究   总被引:1,自引:0,他引:1  
用骤冷法研究FeCl3和Fe2Cl6与KCl的反应热力学,结果显示,在温度(638-788)K和压力(0.001 1-0.006 4)MPa范围内,KFeCl4是唯一气态配合物产物.反应(1/2)Fe2Cl6(g)+KCl(s)=KFeCl4(g)的热力学函数是△H(OI)m(298.15,KFeCl4,g)=(19.6±2.0)kJ·mol-1,△S(OI)m(298.15,KFeCl4,g)=(-8.5±3.0)J·mol1·K-1;反应FeCl3(g)+KCl(s)=KFeCl4(g)的热力学函数是△H(OI)m(298.15,KFeCl4,g)=(-56.9±2.0)kJ·mol-1,△S(OI)m(298.15,KFeCl4,g)=(17.4±3.0)J·mol-1·K-1.  相似文献   

10.
本文报道了新显色剂2-[2-(6-甲基苯并噻唑)偶氮]-5-二甲氨基苯甲酸(6-Me-BTAMB的合成,研究了在十二烷基硫酸钠存在下铁(Ⅱ)与6-Me-BTAMB形成稳定的蓝紫色配合物,其最大吸收峰位于640nm,表观摩尔吸光系数为1.02×10~5 L·mol~(-1)·cm~(-1),Fe(Ⅱ)在0~3.5μg/25ml范围内服从比尔定律.在NaF和硫脲存在下反应具有较好的选择性.方法已用于直接测定铝合金中微量的铁,结果满意.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

15.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

16.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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