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11.
1 INTRODUCTION Organically templated metal phosphates have attracted considerable attention in recent years be- cause of their potential applications in catalysis, ion exchange and separation[1]. Among these, zinc phos- phates constitute an important fam…  相似文献   
12.
开放骨架磷酸铝化合物是多孔晶体材料的一个重要家族。然而,这类材料的合成受到反应原料、凝胶组成、溶剂、模板剂、结晶温度和结晶时间等多个因素的影响。本文以吉林大学“无机制备与合成化学国家重点实验室”建立的开放骨架磷酸铝合成反应数据库为研究对象,采用最大权重最小冗余特征选择算法(Maximum weight and minimum redundancy,MWMR),在充分考虑合成参数自身的重要程度和合成参数之间的相关关系的前提下,分析了溶剂、模板剂等合成参数对于合成含有(8,6)元环结构开放骨架磷酸铝的影响。通过大量实验验证了该方法在开放骨架磷酸铝合成参数分析中的有效性,分析了合成参数对产物生成的影响。实验结果表明模板剂的几何参数、模板剂中C原子和N原子的个数比,溶剂的偶极距等参数可能对于该类结构的合成具有较为重要的影响。  相似文献   
13.
The preparation, crystal structure and properties of a novel 3D coordination polymer Er2(abdc)3·5.5H2O are reported. The rare earth Er2+ ion centers are in the 8-member coordination environment. Carboxylic groups bridge erbium atoms to form these building blocks in a bis-monodentate mode, which expands to construct a 3D framework with two channels intersecting each other. The sorption of these channels was studied.  相似文献   
14.
Open-framework aluminophosphates constitute an important family of materials due to their enormous potential applications in catalysis, exchange and gas separation, such as aluminosilicate zeolites. These compounds, whose formations are promoted by the presence of organic templates, are constructed from alternation of AlO4 and PO4 tetrahedral with an Al/P ratio of unity. However, there are quite a number of AlPOs that contain 5- or 6-coordinated Al atoms which are coordinated to extra-fram…  相似文献   
15.
开放骨架磷酸铝化合物是多孔晶体材料的一个重要家族。然而,这类材料的合成受到反应原料、凝胶组成、溶剂、模板剂、结晶温度和结晶时间等多个因素的影响。本文以吉林大学"无机制备与合成化学国家重点实验室"建立的开放骨架磷酸铝合成反应数据库为研究对象,采用最大权重最小冗余特征选择算法(Maximum weight and minimum redundancy,MWMR),在充分考虑合成参数自身的重要程度和合成参数之间的相关关系的前提下,分析了溶剂、模板剂等合成参数对于合成含有(8,6)元环结构开放骨架磷酸铝的影响。通过大量实验验证了该方法在开放骨架磷酸铝合成参数分析中的有效性,分析了合成参数对产物生成的影响。实验结果表明模板剂的几何参数、模板剂中C原子和N原子的个数比,溶剂的偶极距等参数可能对于该类结构的合成具有较为重要的影响。  相似文献   
16.
A new open-framework zincophosphite, Zn2(HPO3)3(H2DACH 1, was hydrothermally synthesized in the presence of 1,2-diaminocyclohexane (DACH) as structure-directing agent. Its structure was determined by single-crystal X-ray diffraction and further characterized by FTIR, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. Crystal data for 1: Mr = 486.88, monoclinic, space group P21/c with a = 10.2287(11), b = 9.7624(11), c = 16.1686(18) A,β = 92.573(2), V = 1612.9(3) A3, Z = 4, Dc = 2.005 g/cm3, F(000) = 984, μ = 3.314 mm-1 and S = 1.152. The final R = 0.0473 and wR = 0.1121 for 2456 observed reflections with I > 2σ(I). The inorganic layer consisting of four- and eight-membered rings is constructed of alternating ZnO4 tetrahedra and HPO3 pseudo pyramids by sharing vertices. The organic template molecules reside in the interlayer region and interact with the inorganic network through H-bonds.  相似文献   
17.
FeCl2与酸性离子液在乙醇中反应制备得到咪唑硫酸铁簇合物[HMIM]2[Fe2O(SO43(DMSO)2]·0.5DMSO(1)和[HPIM]4[Fe4O2(SO46(DMSO)4]·2MeCN(2),该类簇合物为四核铁簇Fe4(O)2(SO46(DMSO)4结构,4个Fe原子通过中心μ3-O桥、硫酸根上的μ2-O和μ3-O桥连接,形成共平面结构,中间的四核铁簇为-4价,4个质子化的咪唑正离子起电荷平衡作用。该簇合物的晶体结构属于三斜晶系中的P1空间群。变温磁化率测试表明该簇合物具有强的反铁磁性。但在类似的反应条件下,FeCl3在酸性离子液反应没有得到类似的簇合物,而是得到DMSO配合物[FeCl2(DMSO)4][EtSO4]·DMSO(3)。  相似文献   
18.
Using n-propylamine as a template,deioned water and secondary-butanol(butan-2-ol)as solvents,a three-dimensional(3D)open-framework aluminophosphate[C3NH10]·[HAl3P3O13](1)and a two-dimensional layered aluminophosphate[C3NH10]3·[Al3P4O16](2)were crystallized from the initial mixtures with compositions of Al2O3:2.4 P2O5:5.0 n-propylamine:100 H2O/butan-2-ol,respectively.They are characterized by X-ray powder diffraction(XRD),thermogravimetric(TG),and elemental(CHN)analyses and structurally determined by single-crystal X-ray diffraction analysis.Compound 1 crystallizes in the monoclinic space group P21/c with a=0.85831(13)nm,b=1.7677(3)nm,c=1.04353(12)nm,=123.887(9)°,and V=1.3143(3)nm3.Compound 2 crystallizes in the monoclinic space group P21/c with a=1.1313(2)nm,b=1.4874(3)nm,c=1.8020(6)nm,=125.07(2)°,and V=2.4817(11)nm3.The results show that the properties of solvent have a significant influence on the structure-directing effect of n-propylamine in the crystallization of the open-framework aluminophosphates.  相似文献   
19.
研究了Al(i-PrO)3-H3PO4-en-EG体系中,两种具有AlP2O83-计量比的一维链AlPO-CSC和AlPO-ESC之间的结构转变,并对转变过程进行了粉末X射线衍射和组成分析。额外加入的酸或碱是两种链相互转变的推动力。由Al2P2四元环共顶点连接而成的AlPO-CSC链作为结构基元,与过渡金属离子Ni相似文献   
20.
A new lanthanum compound with three-dimensional channels, La2(H2O)(SO4)3 has been synthesized hydrothermally by using 1,2-dizminiopnopane as a structure-directing agent (SDA). The colorless block crystals were characterized by IR, TGA, ICP and XRD. The structure was determined by single-crystal diffraction. The title compound crystallizes in the orthorhombic, P212121(No. 19) with cell parameters, a = 17.095(3) ?, b = 17.331(3) ?, c = 6.8633(12) ?, V = 1659.0(8) ?3, Z = 4, R = 0.0545, wR = 0.1246. The open framework of title compound is built up by LaO10, LaO9 polyhedra and SO4 tetrahedra, connected to form interesting eight-membered ring channels along crystallographic a axis.  相似文献   
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