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121.
Zhaofei Li Junliang Sun Chun-K. Loong Fuhui Liao 《Journal of solid state chemistry》2005,178(11):3315-3322
A powder sample of Sr3FeMoO7 was synthesized by solid-state reaction in reduced atmosphere (5% H2/Ar). At room temperature, Sr3FeMoO7 crystallizes in a typical Ruddlesden-Popper (n=2) structure in the space group I4/mmm, and . The structure refinement indicates that the Fe and Mo ions are randomly distributed in a single B-site with small fraction of B-site and oxygen vacancies. At low temperature, long-range magnetic interaction was observed. The antiferromagnetic magnetic interaction can be described with a large unit cell, and cm=cn, in the magnetic space group An′. 相似文献
122.
The synthesis and characterization of a novel mixed-valent uranium oxyfluoride is described; the inorganic network consists of 2-D [U(2)F(10)](2)(-) sheets constructed from corner- and edge-sharing U(IV)F(9) tricapped trigonal prisms and 1-D [UO(2)F(3)](-) chains constructed from edge-sharing U(VI)O(2)F(5) pentagonal bipyramids with the organic cations and water molecules between the sheets. This is the first example with a hybrid network structure in the system of uranium fluoride or oxyfluoride. The variable-temperature magnetic susceptibility confirms the oxidation state of the uranium ions. Crystal data follow: C(6)H(25)N(4)O(4)F(13)U(3), monoclinic, space group P2(1) (No. 4); a = 8.6876(4) A, b = 7.3158(4) A, c = 16.3376(8) A, beta = 93.7285(9) degrees , V = 1036.2(2) A(3), and Z = 2. 相似文献
123.
124.
Liya?Wang Zhiliang?Liu Chenxi?Zhang Zhanquan?Liu Daizheng?Liao Zonghui?JiangEmail author Shiping?Yan 《中国科学B辑(英文版)》2003,46(6):533-541
A novel one-dimensional manganese(II) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2(μ1,1-N3)(μ1,3-N3) · EtOH]
n
was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(II) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical
and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in
trans axial position. Mn(II) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through μ1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds, π-π interactions and
hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic
interactions between the radical and Mn(II) ion, weak antiferromagnetic interactions between the Mn-R units, and very weak
antiferromagnetic interactions between the R-Mn-Mn-R units. 相似文献
125.
A novel support with artificially created recognition for the selective removal of proteins and for affinity chromatography 总被引:4,自引:0,他引:4
Summary Acrylamide and N,N-methylenebisacrylamide were copolymerized in the presence of a protein to form a gel which was pressed through a sieve. The gel particles obtained were packed into a chromatographic tube. The experimental conditions for the polymerization are such that the pores of the gel particles are large enough to permit the protein to diffuse out of the particles, so that the entrapped protein can be removed from the bed by washing with an aqueous solution. However the interaction with the matrix is so strong that the protein can be desorbed only by a buffer containing 0.5 M sodium chloride or by a 10% solution of acetic acid containing 10% SDS. When a sample containing the protein present during the polymerization was applied to the column along with other proteins this protein was the only one adsorbed. The technique worked selectively with hemoglobin, cytochrome C and transferrin. 相似文献
126.
The self‐assembly of NiCl2·6H2O with a diaminodiamide ligand 4,8‐diazaundecanediamide (L‐2,3,2) gave a [Ni(C9H20N4O2)(Cl)(H2O)] Cl·2H2O ( 1 ). The structure of 1 was characterized by single‐crystal X‐ray diffraction analysis. Structural data for 1 indicate that the Ni(II) is coordinated to two tertiary N atoms, two O atoms, one water and one chloride in a distorted octahedral geometry. Crystal data for 1: orthorhombic, space group P 21nb, a = 9.5796(3) Å, b = 12.3463(4) Å, c = 14.6305(5) Å, Z = 4. Through NH···Cl–Ni (H···Cl 2.42 Å, N···Cl 3.24 Å, NH···Cl 158°) and OH···Cl–Ni contacts (H···Cl 2.36 Å, O···Cl 3.08 Å, OH···Cl 143°), each cationic moiety [Ni(C9H20N4O2) (Cl)(H2O)]+ in 1 is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chainlike structure. Thermogrametric analysis of compound 1 is consistent with the crystallographic observations. The electronic absorption spectrum of Ni(L‐2,3,2)2+ in aqueous solution shows four absorption bands, which are assigned to the 3A2g → 3T2g, 3T2g → 1Eg, 3T2g → 3T1g, and 3A2g → 3T1g transitions of triplet‐ground state, distorted octahedral nickel(II) complex. The cyclic volammetric measurement shows that Ni2+ is more easily reduced than Ni(L‐2,3,2)2+ in aqueous solution. 相似文献
127.
Ruojie Tao Shuangquan Zang Chongzhen Mei Qinglun Wang Benyong Lou Jingyang Niu Yanxiang Cheng Daizheng Liao 《Journal of Cluster Science》2003,14(4):459-469
Two heterometallic trinuclear complexes {[Cu(oxbp)]2Co(H2O)2}1.5DMF0.5H2O (complex 1) and {[Cu(oxbm)]2Co(H2O)2}2DMF (complex 2) were obtained from the self-organization of two new dissymmetrical oxamidato-bridged copper(II) building blocks [Cu(oxbp)]– and [Cu(oxbm)]–[H3oxbp=N-benzoato-N'-(3-aminopropyl)oxamido, H3oxbm=N-benzoato-N'-(2-amino-2-methylethyl)oxamido, DMF=dimethylformamide]. The crystal structure of complex 1 has been determined. Complex 1 crystallize in triclinic system, space group P-1, a=8.0609(16) Å, b=10.661(2) Å, c=22.279(5) Å, =85.32(3), =86.64(3), =70.90(3), and Z=1. The crystal structure of complex 1 consists of neutral trinuclear complex units, and hydrogen bond involved DMF and water molecules. Through the hydrogen bonds, weak coordination and CuCu weak interactions, complex 1 features a 2-D supramolecular structure. Magnetic susceptibility measurements (5–100 K) indicate that the central Co(II) and terminal copper metal ions are antiferromagnetically coupled with J=–28.09 and J=–29.70 cm–1 for complex 1 and 2, respectively. 相似文献
128.
离子交换树脂负载Ni—B无定形合金催化剂的制备与性能 总被引:2,自引:0,他引:2
制备了一种新型离子交换树脂负载的Ni-B无定形合金催化剂.用3种树脂作为催化剂载体,即弱酸型阳离子树脂D152,强酸型阳离子树脂D72及强碱型阴离子树脂D261.用XPS、TEM和ICP等技术对催化剂进行了表征.结果表明,催化剂上镍与带有功能基的载体树脂之间有着很强的相互作用,但其强度与所带的功能基有关.3种催化剂Ni2p3/2的XPS谱图上,NiB/D152催化剂的氧化态峰最小,而NiB/D261的氧化态峰最大.异丙醇脱氢反应活性实验证实了这一结果. 相似文献
129.
MENG Jian REN Yu-Fang LI Xiao-GuangLaboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin ChinaPopov V.V. Repin S.M. Smirnov LA. loffe Physicotechnical Institute Russian Academy of Sciences Saint Petersburg Russia 《中国化学》1994,12(5):419-424
YBa2Cu3-xVxO7-y(x=0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) superconductors have been prepared. X-ray diffraction shows that the system remains orthorhombic for all compositions studied, but for x > 0.4 V2O5 was detected as an impurity phase. Substitution of V5+ for Cu2+ occurs in the Cu(2) sites on the Cu(2)-O planes. The introduction of the high valence element, vanadium, produces the extra free-electrons. These electrons recombine with the positive carrier of the system. It makes depression of the mobility and the Hall number of YBa2Cu3-xVxO7-v and also results in a depression of TC. 相似文献
130.
Huang HC Lee JF Chao HP Yeh PW Yang YF Liao WL 《Journal of colloid and interface science》2005,286(1):127-133
The influence of natural organic matter (NOM) constituents on contaminant distribution coefficients was evaluated by determining the Koc values of aromatic and aliphatic organic compounds (solutes) with clays modified with both aromatic- and aliphatic-rich organic constituents. The studied compounds consisted of naphthalene, phenanthrene, n-pentane, and 2,3,4-trimethylmethane; the solid samples comprised two clays with little organic content, kaolinite and Ca-montmorillonite. Two aliphatic surfactants and three aromatic dyes, sorbed to the clays, served as reference NOM constituents. For solutes of comparable water solubilities, the organic-carbon normalized distribution coefficients (Koc) of the aliphatic solutes between sorbed aliphatic organic matter and aqueous solution slightly exceed those of the aromatic solutes. By contrast, the aromatic solutes exhibited higher Koc values than did the aliphatic compounds with sorbed aromatic-rich organic matter. The difference in Koc values could be attributed to either comparable solubility parameters or the difference in the chemical structure between nonionic organic solutes and specific components of the simulated NOM. The much higher Koc values observed for the aromatic solutes indicate that the NOM composition is a major factor determining the NOC environmental distribution. 相似文献