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1.
羧酸配合物在磁学、光学、催化、生物等诸多领域有广泛的应用前景,羧酸配合物晶体材料的设计、合成、结构及性能的研究一直是人们研究的热点 [1].近年来,我们用刚性芳香羧酸构筑了一些羧酸配合 [2,3],但对于柔性芳香羧酸配体体系我们研究不多 [4].  相似文献   

2.
稀土与羧酸多元配合物具有多种形式的分子构型及配体多面体 ,结构形式多种多样 [1]。它们在光、电、磁、萃取、分离、杀菌剂等很多方面有广泛的应用前景,一直为国内外学者所关 注 [2,3]。稀土和芳香族羧酸能形成聚合网络及链状结构 [4],本文报道了新的链状化合物 [Lu(POA)3(phen)]n的合成与结构,对于丰富稀土配合物不失为一项有意义的工作。 1实验部分 1.1配合物合成 称取氧化镥( Lu2O3)0.1mmol,加入稍过量的 6mol· L- 1 HCl使之溶解,在 80~ 90℃下蒸发至干,加入 5mL水, 5mL乙醇;苯氧乙酸 0.3mmol用 5mL 95%乙醇溶解,以 2…  相似文献   

3.
羧酸配合物在配位化学中占有重要地位.羧酸配合物有丰富的拓扑结构、较高的稳定性,在磁学、光学、催化、生物等诸多领域有广泛的应用前景,羧酸配合物引起了人们广泛的兴趣和极大的关注[1~3].近年来,我们用小位阻的羧酸配体合成了一些羧酸配合物[4~6],而对于大位阻的羧酸配体体系我们研究很少.二苯乙醇酸是一种大位阻的柔性芳香羧酸,文献报道的二苯乙醇酸配合物不多[7-9].  相似文献   

4.
有要锡配合物因基具有很强的生物活性以及多变的结构而日益受到人们的关注[1~4].有关该化合物的结构研究表明,中心锡原子的配位形式决定于直接与锡原子相连接的烃基的结构和羧酸基配体的类型[5~7].为了进一步探索有机锡羧配合物的结构类型、羧酸配体中带额外孤电子对的杂原子与锡原子的作用方式,本文合成了一个有机锡羧酸配合物[Ph3Sn(OCOC5H4NO)]n,并用X-射线衍射单晶结构分析方法测定了它的晶体结构.  相似文献   

5.
羧酸可以采取螯合双齿,桥式双齿,μ3-桥式和单齿等多种形式与稀土离子配位,相应的配合物往往具有层状、无限链状和网层状聚合等特殊结构。羧酸稀土配合物在发光材料、催化和磁性材料等方面均有应用因而受到广泛关注[1-5]。其中芳香羧酸与稀土离子的配合物由于具有优异的发光性能和热稳定性一直是人们研究的热点[6-10]。文献[6-9]对稀土.  相似文献   

6.
羧酸配合物具有丰富的拓扑结构,在磁学、光学、催化、生物等诸多领域有广泛的应用前景,人们对羧酸配合物的研究一直保持着浓厚的兴趣[1,2].  相似文献   

7.
芳香羧酸与金属离子构筑的配合物在材料、药物、分子电化学、生物化学、生物制药等许多领域中潜在的应用价值,因此,芳香羧酸配合物的合成与结构研究一直是人们关注的热点课题之一[1-3].  相似文献   

8.
稀土有机配合物在激光材料创制、结构探针、荧光免疫分析及生物传感器等领域展示出了广阔的应用前景[1].  相似文献   

9.
2,3—二氯异丁酸,邻菲咯啉稀土三元配合物的合成与表征   总被引:2,自引:0,他引:2  
稀土与羧酸形成的多元配合物有许多特殊的结构[1]和发光性能因而受到广泛关注。羧酸及邻菲咯啉与稀土形成的三元配合物中,邻菲咯啉作为获光中心具有“天线效应”[2,3],研究此类稀土多元配合物可以为探索新的光致变色材料提供有用的信息。据文献[1]报道,稀土与邻菲咯啉及羧酸的多元配合物有单核和双聚二种结构,据我们对文献[2~11]的分析,发现形成哪一种结构与反应物是一次性同时加入,还是先制得二元配合物然后再加入另一个配体合成三元配合物的反应过程有关。先制取羧酸稀土二元配合物再加入配体phen一般易得到单核三元配合物[5~9]。本文选…  相似文献   

10.
稀土金属离子氨基多羧酸配合物由于其配位数和结构的多样性,多年来一直是化学家们所感兴趣的内容之一[1-3].例如Sakagami N.等人就曾对稀土金属离子氨基多羧酸配合物做了系统的研究[4],总结出La(Ⅲ)-EDTA形成十配位结构配合物,Ln(Ⅲ)-EDTA(Ln(Ⅲ)指Pr(Ⅲ),Nd(Ⅲ),Sm(Ⅲ),Eu(Ⅲ),Gd(Ⅲ),Dv(Ⅲ)和Ho(Ⅲ)等)形成九配位结构配合物,而Yb(Ⅲ)-EDTA则形成八配位结构配合物.  相似文献   

11.
Solvent extraction studies have been made on some metals: In/III/-Tl/III/ and Hg/II/-Cd/II/-Co/II/, from ammonium thiocyanate solutions by dialkyl sulphoxides. Separation of these metals from one another can be achieved by suitable choice of the extracted conditions. The nature of the extractable metal species has been elucidated.  相似文献   

12.
Summary Single reverse water-gas shift (RWGS) and dehydrogenation of propane with CO2(DH-CO2) reactions in the presence and absence of the CrOx/SiO2 catalyst have been studied between 673 and 873 K. It was found that the CrOx/SiO2 catalyst is active both in the dehydrogenation of propane and in the RWGS reactions. The obtained results suggest that the dehydrogenation of propane to propene in the presence of CO2on CrOx/SiO2can be facilitated by the RWGS reaction.</o:p>  相似文献   

13.
Chlorobis/-diketonato/ oxotechnetium/V/ complexes [TcOCl/-dik/2, -diketone=acetylacetone, benzoylacetone and dibenzoylmethane] were newly synthesized using macroamount of99Tc. These complexes were further separated into geometrical isomers. Furthermore, an improvement of the yields for the syntheses of tris/-dike-tonato/technetium/III/ complexes [Tc/-dik/3, -diketone=acetylacetone, benzoylacetone and 2-thenoyltrifluoroacetone] was examined using Tc/III/-thiourea complexes as a starting material.  相似文献   

14.
Summary CexTi1-xO2 and H3PW12O40/CexTi1-xO2 catalysts were prepared using a sol-gel method, and applied to the direct synthesis of dimethyl carbonate from methanol and carbon dioxide. H3PW12O40/CexTi1-xO2 showed a better catalytic performance than the corresponding CexTi1-xO2, due to the bifunctional catalysis of Br?nsted acid sites (provided by H3PW12O40) and base sites (provided by CexTi1-xO2). H3PW12O40/Ce0.1Ti0.9O2 showed the highest catalytic performance among the H3PW12O40/CexTi1-xO2 catalysts.  相似文献   

15.
The crystal structure of trisodium monophosphate hemihydrate was determined. The space group is C2c and a unit cell contains eight formula units. The unit cell dimensions of Na3PO4 · 12H2O are a = 9.631(3), b = 5.416(2), c = 16.938(8) Å, β = 102.60(5)°. The final R value is 0.027 for a set of 1430 independent reflections. This atomic arrangement is mainly a three-dimensional network of distorted NaO6 octahedra. The hydrogen bonding scheme is given.  相似文献   

16.
LixNi0.8-yCo0.2ZnyOp的合成及电化学性能研究   总被引:1,自引:0,他引:1       下载免费PDF全文
A series of single-phase LixNi0.8-yCo0.2ZnyOp(0.96 ≤x≤ 1.10, 0 ≤y≤ 0.05, 2 ≤p≤ 2(1+y) ) (different in the y values) were synthesized by a two-step solid state reaction method, in which LiOH·H2O, Zn-doped spherical Ni(OH)2 and Co2O3 were used as the precursors. The ICP-AES analyses proved that the Zn-doped compounds synthesized had the nonstoichiometric form. The results of the XRD, SEM identified that the uniform particles of the as-prepared materials having a good layered structure were fine, narrowly distributed and well crystallized. The electrochemical performance test was carried out and the results showed that the as-prepared Zn-doped materials had not only a high capacity, but also a better cycling stability characterization than the un-doped one. The Li1.06Ni0.75Co0.22Zn0.03O2.03 material has an initial reversible capacity as high as 160.5mAh·g-1; and a first discharge efficiency 89.2%, and exhibits satisfactory cyclic stability with 90% retainable capacity after 50 cycles.  相似文献   

17.
Doped-rutile has been traditionally used in ceramic pigments for its intense optical properties. In this paper, we compare the classical ceramic synthesis of Ti1−2xNbxNixO2−x/2 system with the sol-gel methodology, which allows a reduction of the anatase-rutile transformation temperature. The composition was optimised in order to obtain a unique rutile phase with the minimum amount of pollutant Ni(II) and enhanced chromatic coordinates. Incorporation of the doping ions in the rutile structure was corroborated by XRD and Rietveld refinements. The species responsible for the colour mechanism were studied by different techniques. UV-VIS spectroscopy showed the characteristic features of Ni2+ ions, whose existence was corroborated by EPR and magnetic measurements. From these results, (Ni,Nb)doped-TiO2 powder samples can be now shaped as thin films, monoliths, etc. by using sol-gel methodology without modifying their properties. This study introduces new possibilities of coloured TiO2-based solid solutions in new combined advanced applications (colouring agent and photocatalyst, etc.).  相似文献   

18.
Summary A strong promoting effect of the presence of C3H8or C3H6was determined for the combustion of CH4in excess oxygen, over pre-sulfated 1%Pt/g-Al2O3and pre-sulfated 1%Pt-2%Sn/g-Al2O3catalysts.</o:p>  相似文献   

19.
Nitrogen substituted yellow colored anatase TiO2−xNx and Fe-N co-doped Ti1−yFeyO2−xNx have been easily synthesized by novel hydrazine method. White anatase TiO2−δ and N/Fe-N-doped samples are semiconducting and the presence of ESR signals at g ∼1.994-2.0025 supports the oxygen vacancy and g∼4.3 indicates Fe3+ in the lattice. TiO2−xNx has higher conductivity than TiO2−x and Fe/Fe-N-doped anatase and the UV absorption edge of white TiO2−x extends in the visible region in N, Fe and Fe-N co-doped TiO2, which show, respectively, two band gaps at ∼3.25/2.63, ∼3.31/2.44 and 2.8/2.44 eV. An activation energy of ∼1.8 eV is observed in Arrhenius log resistivity vs. 1/T plots for all samples. All TiO2 and Fe-doped TiO2 show low 2-propanol photodegradation activity but have significant NO photodestruction capability, both in UV and visible regions, while standard Degussa P-25 is incapable in destroying NO in the visible region The mid-gap levels that these N and Fe-N-doped TiO2 consist may cause this discrepancy in their photocatalytic activities.  相似文献   

20.
采用高温固相法制备了4种高纯度晶相组成的LixZryOz三元化合物,研究了焙烧温度、时间、反应物的种类和初始反应物物质的量比对产物组成的影响,进一步用XRD、SEM及BET分析方法对产物的晶相结构、表面形貌及比表面积进行了表征.实验结果表明,Li2CO3与ZrO2在适当条件下可以合成得到单斜相Li3ZrO3;以LiOH替代Li2CO3,在适当条件下可以分别合成得到四方相Li2ZrO3和三斜/单斜相Li6Zr2O7;进一步以Zr(NO3)4·5H2O代替Zr02,可将单斜相Li6Zr2O7的制备时间由96 h缩短至24 h.SEM照片显示产物硬团聚明显,粒径分布在1~10μm间,BET分析表明样品比表面积处于1.0~9.0 m2·g-1间分布,反应过程中锂的过量以及长时间高温焙烧是引起产物粒径长大和产生硬团聚的主要原因.  相似文献   

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