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81.
本文合成了1个新的配位聚合物[Zn(apy)(μ-OH)NO3]n(apy=2-氨基嘧啶),并且通过元素分析、红外、荧光、和单晶X-射线进行了表征。标题化合物属于单斜晶系,P21/c空间群,a=0.715 48(14)nm,b=1.850 5(4)nm,c=0.645 68(13)nm,β=110.24(3)°,V=0.802 1(3)nm3,Z=4,R=0.028 4。在化合物中,每个Zn(Ⅱ)离子与氨基嘧啶配体的1个N原子、硝酸根的1个O原子,以及2个羟基氧原子配位,并展示出扭曲的四面体几何构型。2个相邻的Zn(Ⅱ)四面体单元通过羟基氧原子连接形成一维链状结构,该一维链进一步通过氢键和π-π堆积作用形成三维网状结构。室温荧光光谱测定表明该化合物在392 nm处有强的荧光发射。 相似文献
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A novel one-dimensional coordination polymer, [Cd( μ-DPIA)2(H2O)]n (HDPIA=4,5-Diphenylimidazole-1-acetic acid), was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. It crystallizes in the orthogonal space group Pca22 with unit cell parameters: a=1.509 6(3) nm, b=0.611 1(1) nm, c=3.216 4(6) nm, and V=2.967 1(10) nm3, Z=4, R=0.032 7, wR=0.086 7. The Cd atom is seven-coordinated by four O atoms and two N atoms from two chelating DPIA- ligands and one water molecule, and displays a distorted pentagonal bipyramid coordination geometry. Each DPIA- ligand bridges two adjacent Cd atoms, forming a infinite chain along the a axis direction. The Cd…Cd separation within the polymer is 0.765 0(3) nm. A layer structure which parallels to the ab plane is further constructed by hydrogen bonding interactions. CCDC: 254247. 相似文献
85.
A coordination polymer of {[Co(2-OPA)2(4,4′-bipy)(H2O)2]·6H2O}n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG, fluorescence and X-ray single crystal diffraction. The title complex crystallizes in triclinic space group P1, with a=0.856 66(17) nm, b=0.859 58(17) nm, c=1.142 2(2) nm, α=69.64(3)°, β=68.35(3)°, γ=74.88(3)°, and V=0.724 4(3) nm3, Z=1, R=0.064 4, wR=0.159 8. Each Co atom occupies a special position of inversion center and has an octahedral coordination environment, defined by two carboxyl O atoms from two 2-OPA- ligands, two N atoms from two 4,4′-bipy ligands and two water molecules. Adjacent Co(Ⅱ) atoms are bridged by 4,4′-bipy ligands, forming a one-dimensional linetype chain structure. The closest Co…Co distance is 1.142 2(2) nm. The results of TG and fluorescent analysis show that the title coordination polymer is stable under 90.2 ℃ and has three emission peaks at 368, 422 and 484 nm. CCDC: 643626. 相似文献
86.
煤在不同O2/CO2气氛下燃烧硫析出特性研究 总被引:4,自引:0,他引:4
研究了煤在不同氧体积分数、混有CO2气氛下燃烧硫析出特性,结果表明,煤在低氧、混有CO2气氛下燃烧,SO2和H2S析出速率曲线均呈现双峰结构,H2S析出率明显增大,硫析出时间延长;在高氧气氛下,SO2和H2S析出速率曲线均呈现单峰结构,硫析出时间缩短。煤在低氧体积分数、混有CO2气氛下燃烧能够改善煤灰自固硫能力,降低硫的最终析出率;煤在高氧体积分数、混有少量CO2气氛下燃烧与空气气氛下燃烧相比,硫的最终析出率无明显变化。 相似文献
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0IntroductionIn recent years many interests have been focusedon the self-assembly of supramolecular architectures,especially on the coordination polymers with rigid or-ganic aromatic carboxylic acid ligands such as tereph-thalate and benzene tetracarboxyl… 相似文献
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河南登封至鲁山地区大陆地壳剖面磁性结构研究 总被引:3,自引:0,他引:3
本文测试了河南登封至鲁山地区出露的大陆地壳剖面岩石系统的磁学参数,并结合岩石的矿物、化学成分及密度、纵波波速等测试结果进行分析。研究表明,剖面内岩石自早元古代安沟群经晚太古代的登封群至太华群,随着变质等级(或地壳断面的视深度)的增加,磁化率K、天然剩磁J_n及饱和等温剩磁J_r也普遍增加。绿片岩相的安沟群及角闪岩相登封群的变沉积岩与变泥质岩呈现明显的顺磁性特征,其它岩石以亚铁磁性为主。太华群岩石的磁性代表了地壳断面内下地壳岩石的磁性分布,其K,J_n和J_r的平均值分别为6680×10~(-6)SI,0.166A/m及71.78A/m。这些结果与世界上几个出露的高级变质地体岩石磁性的研究结果吻合得很好。 相似文献
90.
A novel coordination polymer, [Cu(m-BDOA)(bipy)·H2O]n (m-BDOA2-=benzene-1,3-dioxyacetate), was synthesized and characterized by elemental analysis, IR spectra, X-ray single crystal structure analysis. Crystallographic data are as follows: orthorhombic, space group Pna21, a=1.606 9(3) nm, b=1.685 9(3) nm, c=0.699 7(1) nm, V=1.8955(7) nm3, Z=4, Dc=1.619 g·cm-3, μ=1.200 mm-1, F(000)=948,R=0.038 1, wR=0.038 6. The copper atom is five-coordinated involving two oxygen atoms of different m-BDOA2- ligand, two nitrogen atoms of 2,2′-bipy ligand and one coordinated water, there is a distorted square pyramidal environment. Two copper atoms are bridged by m-BDOA2- ligand, forming a one-dimensional chain along a axis. The adjacent distance of Cu…Cu atoms is 0.877 3nm. The crystal network was formed by the intermolecular hydrogen bond and π-packing interactions. 相似文献