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21.
采用溶胶凝胶法制备了用于草酸二甲酯加氢合成乙二醇的Cu/SiO2催化剂,在优化的反应条件下,当催化剂中Cu含量为15%~25%时,草酸二甲酯转化率和乙二醇选择性分别达到99.9%和95.0%.通过N2吸附-脱附、透射电镜、X射线衍射、氢气程序升温还原、N2O滴定法和X射线光电子能谱等手段对各Cu/SiO2催化剂进行了表...  相似文献   
22.
A novel zinc coordination polymer,[Zn 2 (bptc)(bpe)(H 2 O)] n (1,H 4 bptc=3,3,4,4-benzophenonetetracarboxylate,bpe=1,2-bis(4-pyridyl) ethane),has been prepared under hydrother-mal conditions.The crystal structure is of monoclinic,space group C/2c with a=27.50(2),b=6.207(4),c=16.233(11),β=107.522(14)°,V=2642 (3)3,C 29 H 22 N 2 O 11 Zn 2,M r=705.27,Z=4,D c=1.773 g/cm 3,F(000)=1432,μ=1.887 mm-1,R=0.0421 and wR=0.1049 for 2594 observed reflections (I > 2σ(I)).X-ray single-crystal diffraction analysis shows that 1 features two-dimensional [Zn 2 (bptc)(H 2 O)] layers,which are further linked by the bpe ligands to give rise to a three-dimensional pillar-layered structure.According to the topology analysis,this framework can be simplified into a (4,6)-connected (4 4 ·6 2)(4 4 ·6 10 ·8) network.  相似文献   
23.
本文考察了新合成的两个二元羧酸取代的三核钼衍生物Mo3S4(DTP)3(phthalate)(Py)(A)(DTP=diethyl dithiophosphate,「S2P(OEt)2」^-)和Mo3S4(DTP)3(malonate)(Py)(B)的红外吸收光谱,对Mo-S键及配体的主要吸收峰进行了归属和讨论,并与化合物Mo3S4(DTP)4(Py)(C)的谱图进行了比较。结果表明,通过对这类复  相似文献   
24.
The title compound {Cu2(pdc)2(4,4′-bipy)(H2O)(3H2O}2 1 (H2pdc = pyridine-2,6- dicarboxylic acid, also known as dipicolinic acid; 4,4′-bipy = 4,4′-bipyridine) has been synthesized by the hydrothermal reaction and its structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pī with a = 7.2278(3), b = 10.6259(4), c = 17.7614(6)A, α= 79.5990(10), β = 83.6300(10), γ = 71.8280(10)o, V = 1272.60(8)A3, C48H44Cu4N8O24, Mr = 1371.07, Z = 1, Dc = 1.789 g/cm3, μ = 1.747 mm-1, F(000) = 696, R = 0.0397 and wR = 0.1137 for 3938 observed reflections (I > 2σ(I)). There are two kinds of Cu coordination environments, and each central copper(II) atom is five-coordinated in a distorted square-based pyramidal coordination geo- metry. Four copper(II) atoms are linked by four pdc and two 4,4′-bipy ligands to form an annular rectangle structure. Extensive hydrogen-bonding interactions involving carboxylate O atoms as well as coordinated and free water molecules lead to the formation of a three-dimensional network struc- ture.  相似文献   
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