共查询到18条相似文献,搜索用时 62 毫秒
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超大孔Fe和V—Ti分子筛的合成 总被引:1,自引:0,他引:1
水热法合成了具有超大孔MCM-41分子筛结构的含Fe和V-Ti分子筛,通过XRD,骨架IR,ESR,^29SiMAS NMR,紫外漫反射等测试表征证实,Fe原子在FeMCM-41分子筛骨架上,V和Ti同是进入V-TiMCM-41分子筛骨架。 相似文献
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柠檬酸盐法合成钙钛矿型复合氧化物纳米固体材料LaFeO_3 总被引:3,自引:0,他引:3
纳米固体材料(或称毫微晶材料)是近几年发展起来的新兴材料,这是由尺寸为纳米数量级(通常粒径<10~15 nm)的微晶颗粒聚集而成的块状或者薄膜人工固体,其原子排列状态既不同于传统的晶态、非晶态,又不同于尺寸为纳米数量级的超微粒,其结构特点使该材料具有与传统材料极不相同的特殊性能,已引起世界各国科学家的高度重视,但是由于 相似文献
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合成了α-和β-三钒九钨锗酸钾,并用元素分析、红外光谱和紫外光谱、~(51)V和~(183)W核磁共振、极谱和循环伏安、热分析及单晶衍射等方法进行了表征。结果表明,这些新化合物具有与GeW_(12)相似的结构;3个钒原子属于不同的M_3O_(13)单元且彼此共角相连。与钨锗酸盐相比,三钒取代的钨钒锗酸钾的热稳定性降低而氧化性增强。 相似文献
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SrTi1—xSnxO3的水热合成与结构研究 总被引:1,自引:3,他引:1
采用水热晶化法合成出SrTi1-xSnxO3系列化合物,并对其结构进行了表征。结果表明,随着Sn含量的增加,产物的晶胞体积增大,红外吸收谱带发生劈裂,并向高波数方向移动。 相似文献
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H4PMo11Vo40杂多酸及其镧盐的合成与性质 总被引:3,自引:0,他引:3
本文提出主要用~(51)V NMR、CV并辅以IR、XRD、DTG、元素分析等作为有效地核查纯度和表征催化剂的手段。 相似文献
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安替比林 ( AP)衍生物可用于稀土的分析测定及协同萃取[1] ,安替比林稀土配合物的合成 [2 ] 及其发光性质和磁学性质等 [3,4 ]的研究已有报道 .在对具有芳基侧链的 4- (邻氯苯甲酰基 )氨基安替比林 [5]、4- (对氯苯甲酰基 )氨基安替比林 [6] 及长链桥联的 N ,N -二安替比林 - 1 ,6-己二酰二胺[7,8] 等与稀土盐相互作用进行研究的基础上 ,本文对短链桥联的 N,N -二安替比林乙二酰二胺与镧系高氯酸盐在水溶液中全浓度范围内的相互作用进行了研究 .1 实验部分1 .1 试剂及仪器 L a( Cl O4 ) 3· 8H2 O用 La2 O3( 99.9% )和 1∶ 1高氯… 相似文献
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Vanadium sesquioxide (V2O3) nanopowder was successfully prepared by the solid phase reaction of the mixture of vanadyl hydroxide (VO(OH)2) and ammonium chloride (NH4Cl) at 500 ℃. The as-obtained samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). V2O3 nanoparticles were well dispersed and displayed sphere-like particles with diameters in the range of 30~50 nm. 相似文献
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C. Wessel C. Reimann A. Müller D. Weber M. Lerch T. Ressler T. Bredow R. Dronskowski 《Journal of computational chemistry》2012,33(26):2102-2107
A metastable bixbyite‐type polymorph of vanadium sesquioxide, V2O3, has recently been synthesized, and it transforms to the corundum‐type phase at temperatures around 550 °C. The possibility of a paramagnetic to canted antiferromagnetic or even spin‐glass‐like transition has been discussed. Quantum‐chemical calculations on the density‐functional theory level including explicit electronic correlation confirm the metastability as well as the semiconducting behavior of the material and predict that the bixbyite‐type structure is about 0.1 eV less stable than the well‐known corundum‐type phase. Nonetheless, quasiharmonic phonon calculations manifest that bixbyite‐type vanadium sesquioxide is a dynamically stable compound. Other possible V2O3 polymorphs are shown to be even less suitable candidates for the composition V2O3. © 2012 Wiley Periodicals, Inc. 相似文献
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Summary From the reaction systemsCyclam/Mecyclam-KVO3-H2O-HCl-EtOH (Cyclam=1,4,8,11-tetraazacyclotetradecane; Mecyclam=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane), the first polyvanadates with cations of macrocyclic amines were isolated: (CyclamH2)2-H2V10O28·2H2O, (MecyclamH2)2H2V10O28·6H2O, (CyclamH2)(VO3)2·3H2O, (CyclamH2)(VO3)2·2H2O, and (MecyclamH2)(VO3)2·H2O. The metavanadates with theCyclamH
2
2+
cation differ markedly in their IR spectra, obviously due to the different structure of the polyanion. The interruption of dynamic heating at the thermal analysis of the crystallohydrates of dihydrogendecavanadates resulted in the formation of corresponding anhydrous dihydrogendecavanadates.
Metavanadate und Dihydrogendecavanadate mit Kationen aus makrocyclischen Tetraaminen
Zusammenfassung Aus demCyclam/Mecyclam-KVO3-H2O-HCl-EtOH Reaktionssystem (Cyclam=1,4,8,11-tetraazacyclotetradecane;Mecyclam=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetrazacyclotetradecane) wurden die ersten Polyvanadate mit cyclischen Aminen als Kationen isoliert: (CyclamH2)2V10O28·H2O, (MecyclamH2)2H2V10O28·6H2O, (CyclamH2)(VO3)2·3H2O, (CyclamH2)(VO3)2·2H2O und (MecyclamH2)(VO3)2·H2O. Die zwei Metavanadate mit dem KationCyclamH 2 2+ unterscheiden sich wesentlich in ihren Infrarotspektren, was auf unterschiedliche Polyanionstruktur der Metavanadate hinweist. Durch Unterbrechen der dynamischen Erhitzung bei der thermischen Analyse von Kristallhydraten der Dihydrogendekavanadate wurden entsprechende Verbindungen ohne Kristallwasser gewonnen.相似文献
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改进的直接萃取法制备环烷酸钕 总被引:1,自引:1,他引:1
改进的直接萃取法制备环烷酸钕杨继华,逄束芬,龚志(中国科学院长春应用化学研究所长春130022)关键词环烷酸钕,直接萃取法,氢氧化钠环烷酸钕是制备稀土合成橡胶常用的催化剂组分之一,可采用固体法、间接萃取法和目前一般采用NH4OH作用下的直接萃取法制备... 相似文献
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结晶碳酸钕的水热合成、外观形貌及其组成 总被引:1,自引:0,他引:1
Crystalline neodymium carbonates were prepared by treating the amorphous precipitate formed from the reaction between neodymium chloride and ammonium bicarbonate under hydrothermal condition. Their composition, morphology and crystal phase were identified by means of elemental analysis, SEM and XRD. It was found that Nd2(CO3)3·2.5H2O with tengerite-type structure and sheet morphology was obtained when the feed molar ratio(FMR=n(NH4)2CO2/nNdCl3)was 2 or 1.8 and hydrothermally treated at 150 ℃ for 12h. However, orthogonal NdOHCO3 particles agglomerated with long rod crystals were formed when lowering FMR to 1.5 under the same hydrothermal condition. Phase transformation from tengerite-type Nd2(CO3)3·2.5H2O to orthogonal NdOHCO3 was occurred when increasing hydrothermal temperature or prolonging hydrothermal time, which is beneficial to the preparation of neodymium hydroxyl-carbonate with neodymium oxide content higher than 70%. 相似文献