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1.
钨磷、钨硅杂多酸及其盐是重要的酸催化剂,它们都含有B酸中心,它来源于结构内质子、阳离子电场中结晶水离解出的质子,可在还原金属离子(如Ag~+)过程中释放出H~+。也有杂多酸(盐)含有L酸的报道,认为它来源于易于接受电子对的抗衡金属阳离子,如AlPW_(12)O_(40)中的Al~(3+),以及在高温加热中发生部分Mo=O或Mo—O—Mo键解体后裸露出的Mo表  相似文献   

2.
采用离子交换法将过渡金属离了三元取代钨杂多阴离子引入Zn2Al型阴离子粘土层内,得到柱撑水滑石Zn2Al(OH)6-SiW9Z3O40(Z=Ti^4+,Mo^6+)及Zn2Al(OH)6-SiW9Fe3(H2O2)3O37。ZRD及IR表明,杂多阴离子引入水滑石层间后,水滑石层内高度为1.0nm。  相似文献   

3.
合成了通式为K_(13)[Ln(β_i-SiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Gd,Er;β_i=β_1,β_3)的两个系列的β-异构体。通过元素分析、极谱、循环伏安法,UV和VIS光谱、磁化率以及热分析等手段研究了异构体的组成和性质。  相似文献   

4.
单氧桥双铁化合物L_5Fe—O—FeL_5已有报道.但有关含杂多阴离子的桥氧二聚体XM_(11)M′—O—M′XM_(11)的报道则甚少.本文合成了3种杂多阴离子二聚体(SiMW_(11))_2O(M=Fe~(Ⅲ),Cr~(Ⅲ),Al~(Ⅲ)),并用XPS、UV、IR及磁化率测定等手段对其性质进行了研究.  相似文献   

5.
三取代钨硅杂多配合物的磁性*王力刘宗瑞周云山王恩波**(东北师范大学化学系长春130024)关键词钨硅杂多化合物磁性Jg中图分类号O641.4杂多化合物具有独特的结构,因此具有许多优异性能,尤其是混配取代型杂多化合物[1],具有优异的热稳定性、氧化还...  相似文献   

6.
镧系元素钨硼杂多酸盐的合成及性质研究   总被引:3,自引:0,他引:3  
钨硼杂多配合是一类性能良好的催化剂,它还具有抗病毒作用,也可用于乳糖酶分离、纤维素光解剂及用于制造耐热油漆等,本文报道了K_(15)[Ln(BW_(11)O_(39))_2]·xH_2O(简称  相似文献   

7.
报道A-β-M'xHy-[GeWOM3(H2O)3O37].nH2O(M=Cr^3^+,Co^2^+,Ni^2^+,Cu^2^+;M'=Bu4N^+,K^+)的立体有择合成法制备及红外和远红外光谱,紫外和可见光谱和循环伏安,磁化率和磁矩,XPS,ESR以及催化活性等研究结果。  相似文献   

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10.
铌取代型钨硅杂多酸盐的合成及抗病毒活性研究   总被引:14,自引:4,他引:10  
杂多化合物因具有独特的结构和优异的抗病毒活性[1,2],近年来受到普遍重视,但研究的热点主要集中在抗艾滋病毒(HIV)、疱疹病毒(HSV)、抗肿瘤等方面[3,4],而忽视了对植物病毒防治的研究。  相似文献   

11.
合成了掺杂Ti、Zr、Mn、Cu、Mo、Cr、和Co过渡金属离子的中介孔分子筛MCM-48.通过TEM、孔分布测试、XRD、电子能谱、红外吸收及热失重分析对掺杂的MCM-48进行结构表征,并研究了其催化性能.结果表明,掺杂Ti、Cr、Zr的MCM-48具有优良的催化性能.  相似文献   

12.
IntroductionThe investigation of organic photochromic materials has increased considerably in recentyears because of their potential commercial application in several areas,such as high-densityoptical storage media,optical switching,etc.[1 ,2 ] .Though numerous organic photochromicmolecular systems or photoactive devices have been explored so far,those systems classifiedaccording to the photochromic structural units mainly belong to a small number of families:fulgides,spiropyrans and spiroxazi…  相似文献   

13.
Powder samples and single crystals of the borides M0.5Ru6.5B3 (M = Cr, Mn, Co, Ni) were synthesized by arc‐melting the elements in a water‐cooled copper crucible under argon. The new phases were structurally characterized by single‐crystal and powder X‐ray diffraction as well as EDX‐Analyses. They crystallize in the hexagonal Th7Fe3 structure type (space group P63mc, no. 186, Z = 2) and a pronounced site preferential M/Ru substitution is observed. Magnetic properties of the compounds were investigated and Pauli paramagnetism was observed in all cases. However, a strong temperature dependency is subsequently observed in Mn0.5Ru6.5B3 below 250 K, but no hint of magnetic ordering was found.  相似文献   

14.
采用缓慢蒸发溶剂法在水中合成了2个含双磺酸基的化合物A-2,5-DSA·(Hphen)2·2H2O(1)和[Co(phen)2(H2O)2]·(A-2,5-DSA)·3H2O(2)(A-2,5-DSA=苯胺-2,5-二磺酸根离子,phen=1,10-邻菲罗啉)。化合物1中,相邻的质子化的1,10-邻菲罗啉反向堆叠在一起,水分子通过氢键与(Hphen)+和苯胺-2,5-二磺酸根离子相连,形成二维的层状结构。配合物2中,钴离子与2个1,10-邻菲罗啉和2个水分子配位,构成[Co(phen)2(H2O)2]2+阳离子。3个自由的水分子通过氢键将苯胺-2,5-二磺酸根离子和[Co(phen)2(H2O)2]2+连接形成三维网状结构。两个化合物中苯胺-2,5-二磺酸根离子均起到平衡电荷的作用。室温下2个化合物均具有荧光性质,其最大发射峰分别在601nm和441nm。  相似文献   

15.
采用缓慢蒸发溶剂法在水中合成了2个含双磺酸基的化合物A-2,5-DSA·(Hphen)2·2H2O(1)和[Co(phen)2(H2O)2]·(A-2,5-DSA)·3H2O(2)(A-2,5-DSA=苯胺-2,5-二磺酸根离子,phen=1,10-邻菲罗啉)。化合物1中,相邻的质子化的1,10-邻菲罗啉反向堆叠在一起,水分子通过氢键与(Hphen)+和苯胺-2,5-二磺酸根离子相连,形成二维的层状结构。化合物2中,钴离子与2个1,10-邻菲罗啉和2个水分子配位,构成[Co(phen)2(H2O)2]2+阳离子。3个自由的水分子通过氢键将苯胺-2,5-二磺酸根离子和[Co(phen)2(H2O)2]2+连接形成三维网状结构。两个化合物中苯胺-2,5-二磺酸根离子均起到平衡电荷的作用。室温下2个化合物均具有荧光性质,其最大发射峰分别在601 nm和441 nm。  相似文献   

16.
缩氨基脲、缩氨基硫脲既是很好的金属离子配体,又有很好的生物活性,如抗细菌、病毒、抗结核、抗麻疯病、抗风湿、抗嗜眠等,文献曾有一些报道。其中有些在结构上调整,引入二茂铁基,显示了一些特殊性质。本文在此基础上进一步合成了12个新型结构的含二茂铁基的缩氨基脲(或硫脲),对它们的性质作了初步研究。  相似文献   

17.
含苯氧基萘并萘醌和偶氮苯双变色基化合物的合成和性质   总被引:2,自引:0,他引:2  
通过6-氯-5,12-萘并萘醌与4-羟基偶氮苯及其衍生物的反应合成了3种含苯氧基萘并萘醌和偶氮苯光致变色基的双变色基化合物,6-[4-(苯偶氮基)苯氧基]-5,12-萘并萘醌(5),6-[4-(p-乙氧基苯偶氮基)苯氧基]-5,12-萘并萘醌(6)和6-[4-(p-硝基苯偶氮基)苯氧基]-5,12-萘并萘醌(7).这些化合物的苯氧基萘并萘醌变色基的UV诱导光致变色性较弱;基于氨与苯氧基萘并萘醌ana显色体的不可逆反应,化合物5和6DMSO溶液在365nm紫外光辐照光稳态(PSS)下的ana醌式摩尔分数估计分别为22%和17%.这些结果说明,苯偶氮基对苯氧基萘并萘醌变色基的光致变色性质有着极强的影响.另一方面,与4-羟基偶氮苯母体不同,这些双变色基化合物在DMSO中偶氮苯变色基的顺式异构体是相对稳定的  相似文献   

18.
Blue luminescent compounds T1-T4 containing triphenylamine donors,bipyridine acceptors and olefinic linkers were synthesized and characterized by 1H NMR,13C NMR and high resolution mass spectrometry(HR...  相似文献   

19.
A series of transition metal coordination polymers [Co(H3L)2(4,4′- bpy)(H2O)2]n?n(4,4′-bpy) (1), [Ni(H2L)(4,4′-bpy)(H2O)2]n (2), [Co2(L)(phen)2(H2O)4]n?(H2O)2n (3), and [Ni2(L)(phen)2(H2O)4]n?(H2O)2n (4) have been assembled from a semirigid multicarboxylate ligand 3,3′-(1,4-phenylenebis(oxy))diphthalic acid (H4L) with the help of 4,4′-bipyridine (4,4′-bpy) ligand or 1,10-phenanthroline (phen) ligand. X-ray single crystal diffraction analysis reveals that complex 1 crystallizes in the space group of P − 1 and displays a one-dimensional (1D) chain structure constructed from 4,4′-bpy ligand and H3L ligand, which was further interlinked to form a three-dimensional network via hydrogen bonds. In complex 2, Ni(II) atoms are coordinated by L ligand in monodentate fashion to form alternate left- and right-helices, which are further bridged together by the coordination interactions between Ni(II) atoms and 4,4′-bpy, leading to a 2-fold (4, 4)-connected interpenetrating network. Isostructural complexes 3 and 4 belong to the space group P − 1 and display a 1D chain structure constructed from phen and L ligands, which was further interlinked to form a 2D plane via π–π interactions. In addition, their thermal and luminescent properties were also investigated.  相似文献   

20.
Complexes of Mn(II), Co(II), Ni(II), Pd(II) and Pt(II) were synthesized with the macrocyclic ligand, i.e., 2,3,9,10-tetraketo-1,4,8,11-tetraazacycoletradecane. The ligand was prepared by the [2 + 2] condensation of diethyloxalate and 1,3-diamino propane and characterized by elemental analysis, mass, IR and 1H NMR spectral studies. All the complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, IR, electronic and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II), Co(II) and Ni(II) complexes in DMF correspond to non electrolyte nature, whereas Pd(II) and Pt(II) complexes are 1:2 electrolyte. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II), Co(II) and Ni(II) complexes, whereas square planar geometry assigned for Pd(II) and Pt(II). In vitro the ligand and its metal complexes were evaluated against plant pathogenic fungi (Fusarium odum, Aspergillus niger and Rhizoctonia bataticola) and some compounds found to be more active as commercially available fungicide like Chlorothalonil.  相似文献   

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