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1.
11—系列杂多钨硅酸盐异构体的氧化还原性质研究   总被引:1,自引:0,他引:1  
通过极谱和循环伏安法,结合红外光谱、紫外光谱和X射线光电子能谱,研究了通式为β2—K6—nHn[SiW11M(H2O)O39]·xH2O(M=Mn2+.Fe3+,Co2+,Ni2+Cu2+Zn2+)杂多钨硅酸盐在溶液中的氧化还原性质,杂多阴离子的极谱半波电位E1/2。顺序为Cu2+>Mn2+>Fe2+>Zn2+>Co2+>Ni2+.发现杂多阴离子的半波电位E1/2与其组分中的过渡元素的电负性X有线性关系,讨论了过渡元素对杂多阴离子氧化还原性的影响。  相似文献   

2.
取代型钨硅杂多化合物的导电性及磁性   总被引:2,自引:1,他引:1  
合成并表征了过渡金属取代的钨硅杂多化合物α-Nan〔SiW9M3(H2O)3O37〕·18H2O〔M=Mn(Ⅱ),Cu(Ⅱ),Fe(Ⅲ)〕(简写α-SiW9M3,以下类同)和α-Nan〔SiW11MO39(H2O)〕·18H2O,在室温下,α-SiW9Fe3的电导率σ值可达10-3S·cm-1,343K时可达10-2S·cm-1,表明是一类新型高质子导体,磁分析表明,α-SiW9M3具有磁性.  相似文献   

3.
合成了过渡金属三取代的钨镓杂多配合物α-NamHn〔GaW9M3(H2O)3O37〕·16H2O(M=Fe(Ⅲ),Zn(Ⅱ),Cr(Ⅲ)),杂多化合物通过红外、紫外、ICP、TG-DTA、EPR、XPS等手段进行表征。电导率结果表明,该类化合物是一类未见文献报道的新型高质子导体。这类化合物可望成为新型无机分子功能材料。  相似文献   

4.
利用控制电位电解的方法合成了4种未见文献报道的杂多蓝,K11H2〔Ln(AwW1O39)2〕·xH2O(Ln=La,Ce,Pr,Nd),并利用等离子体原子发射光谱等对其进行了元素组成的分析,利用IR、UV、极谱,光电子能谱,电子顺磁共振,热重差热等测试手段,对其结构和性质进行了研究。  相似文献   

5.
利用控制电位电解的方法合成了4种未见文献报道的杂多蓝,K11H2〔Ln(AsW11O39)2〕·xH2O(Ln=La,Ce,Pr,Nd),并利用等离子体原子发射光谱等对其进行了元素组成的分析,利用IR、UV、极谱、光电子能谱、电子顺磁共振、热重差热等测试手段,对其结构和性质进行了研究.  相似文献   

6.
几种含铁化合物对煤燃烧特性的影响   总被引:9,自引:0,他引:9  
利用热重-差热-热重微分仪实验研究了几种含铁化合物,如FeCl3、FeCl2和Fe2O3等对煤燃烧特性的影响。结果表明,含铁化合物能够发迹煤的燃烧特性,不同种类的含铁化合物对煤燃烧特性的影响不同。FeCl3和FeCl2能够提高煤燃烧过程低温段的燃烧反应速率,其机理是FeCl3和FeCl2起催化剂的作用,改变了燃烧过程化学反应的动力学参数,从而加快了煤的燃烧速率。FeCl3和FeCl2的催化能力随其  相似文献   

7.
硅基取代环戊二烯基二羰基铁负离子[η^5-RC5H4Fe(CO)2]^-(R=SiMe3,I;Si2Me5,Ⅱ)与铁碘化合物(η^5-C5H5)Fe(CO)2I反应,除得到新的Fe-Fe化合物外,还分离到另两种母体Fe-Fe化合物;桥连化合物(η^5,η^5-C5H4SiM32OSiMe2C5H4)[Fe(CO)2I]2(6)与铁负离子[η^5-C5H5Fe(CO)2]^-(Ⅲ)的反应,仅分离到各  相似文献   

8.
空气氧化湿法制备的MnFe2O4在H2还原下,生成氧缺位铁酸锰MnFe2O4-δ,利用XRD和Mossbauer谱等技术,对它的性质(还原性,晶格常数稳定性)进行了详细地研究,考查了在氧缺位铁酸锰(MnFe2O4-δ,δ〉1)及MnO-FeO固溶体下CO2分解成C的活性,结果表明能够有效地分解CO2成C,并且在反应以后自身转变成为化学计量的MnFe2O4,MnO4-FeO分解CO2以后,一部分变成  相似文献   

9.
空气氧化湿法制备的MnFe2O4在H2还原下,生成氧缺位铁酸锰MnFe2O4-δ(0<δ<1),利用XRD和Mossbauer谱等技术,对它的性质(还原性,晶格常数稳定性)进行了详细地研究,考查了在氧缺位铁酸锰(MnFe2O4-δ,δ>1)及MnO-FeO固溶体下CO2分解成C的活性,结果表明(MnFe2O4-δ,δ>1)能够有效地分解CO2成C,并且在反应以后自身转变成了化学计量的MnFe2O4,MnO-FeO分解CO2以后,一部分变为MnFe2O4,一部分仍然保持MnO-FeO固溶体结构  相似文献   

10.
利用控制电位电解的方法合成了8种未见文报道的Dawson结构的钨砷稀土杂多蓝:Ln2H2As2W18O62·xH2O(2e杂多蓝)和Ln2H4As2W18O62·xH2O(4e杂多蓝),其中Ln=La,Ce,Pr,Nd。通过红外光谱,紫外光谱,极谱,光电子能谱、顺磁共振,热重-差热重对其进行了表征,并进行了结构和性质的研究。结果表明,还原前后杂多酸盐的结构虽有轻微的变化,但热稳定性和在溶液中的稳定  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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