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1.
通过水热方法合成了2个夹心型磷钼簇基有机-无机杂化化合物(C4H14N3)(C4H15N3)4{Na[Mo6ot5(H2PO4)4]2)·8H2O(化合物1)和{Ni[Mo6O15(H2PO4)4]2}(4,4'-bipy)3·H2O(化合物2,其中4,4'-bipy为4,4'-联吡啶),并对其进行元素分析、红外光谱和...  相似文献   

2.
用哌嗪和丙胺作模板剂在水热条件下合成了微孔材料NH4[Ni(H2O)2Al2(PO4)3];单晶解析表明该结构与以往的金属磷酸铝大有不同,结构中的镍原子是八配位的,且与铝的位置区别明显;单晶结构数据,元素分析,拉曼光谱表明NH4[Ni(H2O)2Al2(PO4)3]材料的八元环孔道中只含有NH4 离子;热重分析和焙烧后的XRD图谱显示,该材料在350℃和空气条件下焙烧2 h,仍然保持其原来的骨架结构;若焙烧温度为550℃,则结构被破坏.  相似文献   

3.
水热体系中制备了(C4H12N2)·[Zn(2-x)Cox(PO4)2](x=0.874)单晶,并对其结构进行了解析.该化合物由ZnO4和PO4四面体通过共顶点相连,形成二维层状结构;双质子化的结构导向剂哌嗪排列在无机层之间.该晶体属于三斜晶系,空间群为PI,Mr=403.20,a=0.514 04(12)nm,b=1.076 0(3)nm,c=1.079 3(3)nm,V=0.541 1(2)nm3,Z=2,d=2.475 g/cm3,μ=4.167 mm-1,R=0.031 3,Rw=0.080 9.  相似文献   

4.
通过水热合成法合成了一个新的夹心型钼磷酸基“三明治”状有机一无机杂化化合物[C3N2H5]2[C7NH10]2{MnFMo8O12(OH)°(PO4)(H2PO4)3]2}[C5NH5]4·2H2O(化合物1),并对其进行元素分析、红外光谱、热重分析和X射线单晶衍射表征。单晶结构解析表明,该化合物属于正交晶系,Pbca空间群,晶胞参数a=1.69774(17)nm,b=2.0438(2)nm,c-2.5047(3)nm,a-90°,B=90°,y=90°,V=8.6908(15)nm3,Z=4。化合物1中的夹心结构阴离子是由2个{MnEM06O12(0H)3(PO4)(H2PO4)3]2}建筑单元通过1个八面体配位的金属Mn2+离子键连形成。化合物[C3N2H5]2[C1NH10]2{MnEMo6O12(OH)3(PO4)(H2PO4)3]2}[GNH5]4·2H2O中,具有夹心结构的Mn(P4Mo6)2与质子化的咪唑、N-乙基吡啶、吡啶及水分子通过氢键连接形成超分子化合物。室温固态荧光光谱分析表明,该化合物在437nm处具有较强的荧光发射。化合物1的合成表明溶剂在多金属氧酸盐的合成中起到了重要的作用。  相似文献   

5.
Al(H2PO4)3溶液表面包覆提高镁钙熟料抗水化性能研究   总被引:1,自引:0,他引:1  
采用浸渍法,以Al(H2PO4)3,Al(H2PO4)3-H3PO4和H2PO4三种溶液为浸渍剂,对镁钙熟料进行表面处理,研究其抗水化性能的变化规律。结果表明,采用Al(H2PO4)3溶液取代或部分取代H2PO4溶液,控制合适的浸溃浓度、反应温度和热处理温度,因在镁钙熟料表面形成了以难溶或不溶于水的Ca2R2O7、Ca3(PO4)2、Al(PO3)3、AlPO4为主的保护膜,同时因为钙和铝的磷酸盐相互交叉构成网络结构,改善了膜的强度及对熟料颗粒表面的粘结性,从而获得优于H3PO4溶液处理的抗水化效果;处理后的镁钙熟料水化增重率和粉化率:Al(H2PO4)3-H3PO4溶液分别为0.35%和2.8%,Al(H2PO4)3溶液分别为0.54%和3.45%,而H3PO4溶液分别为0.41%和5.1%。  相似文献   

6.
以LiOH·H2O,NH4H2PO4和V2O5为原料,加入导电碳,用高温固相法合成Li3V2(PO4)3;以LiOH·H2O,NH4H2PO4,NH4VO3为原料,柠檬酸作为还原剂和碳源,用溶胶凝胶法合成Li3V2(PO4)3,并对材料的化学电化学性能进行了研究.  相似文献   

7.
以氧化钙和磷酸为起始原料合成骨灰瓷原料.采用XRD和SEM方法表征了合成料的晶相与显微结构,探讨了不同Ca/P的比值对结构的影响.结果表明:合成料存在α-Ca3(PO4)2、β-Ca3(PO4)2、Ca10(PO4)6(OH)2和CaO四个晶相.Ca/P比值从1.0→1.6,β-Ca3(PO4)2含量增加,α-Ca3(PO4)2含量降低;Ca/P比值从1.6→2.0,β-Ca3(PO4)2含量降低,而α-Ca3(PO4)2含量增加;Ca/P=1.6时,β-Ca3(P4)2含量最高,因此选择其为最佳的配方.对应的晶相含量(质量分数)分别为:β-Ca3(PO4)2为76.0%,α-Ca3(PO4)2为6.6%,Ca10(PO4)6(OH)2为9.2%,CaO为7.7%.  相似文献   

8.
以硝酸银和十二水磷酸钠为原料,150℃水热条件下反应24 h制备出了多面体Ag3PO4。对产物的结构进行了X-射线粉末衍射(XRD),扫描电子显微镜(SEM),荧光(FL)光谱表征,分析了在水热条件下AgNO3浓度﹑反应时间、反应温度和溶液的pH对产物形貌的影响。X-射线粉末衍射分析表明得到的产物为纯净的立方相Ag3PO4,通过扫描电镜观察到产物形貌主要为多面体结构。  相似文献   

9.
以硝酸银和十二水磷酸钠为原料,150℃水热条件下反应24 h制备出了多面体 Ag3 PO4。对产物的结构进行了X-射线粉末衍射(XRD),扫描电子显微镜(SEM),荧光(FL)光谱表征,分析了在水热条件下AgNO3浓度﹑反应时间、反应温度和溶液的pH 对产物形貌的影响。 X-射线粉末衍射分析表明得到的产物为纯净的立方相 Ag3 PO4,通过扫描电镜观察到产物形貌主要为多面体结构。  相似文献   

10.
为处理核工业生产中的高质量浓度氟氨废水,采用序批式烧杯试验,分别考察了除氟脱氨顺序、混合液pH值、药剂投量等因素对反应过程的影响,探索通过生成CaF2和Mg(NH4)PO4(MAP)强化除氟脱氨的方法.结果表明,先脱氨后除氟时,Ca2+会争夺MAP中的PO3-4转化为Ca3(PO4)2,释放NH4+降低脱氨效率.先除氟后脱氨时,控制nMg2+:nPO3-4:nNH4+为1.1:1.075:1.0,混合液pH值为10.0,能实现理想的除氟脱氨.其中脱氨时投加的PO3-4会与Ca2+和F-生成溶解度很低的Ca5(PO4)3F,是强化除氟的关键.适当超投一些PO3-4可以强化脱氨,对于混合液中残存的PO3-4,可在沉淀后上清液中投加少量Ca2+生成Ca3(PO4)2进而去除.  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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