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991.
A novel 3D polymeric heteropolynuclear sodium(I) lead(II) complex containing different ligands, [NaPb(ClO4)(en)(NO2)2] was synthesized and characterized by elemental analysis and IR, and 1H‐, 13C‐, and 207Pb‐NMR spectroscopy. The single‐crystal X‐ray data of [NaPb(ClO4)(en)(NO2)2]n established that the complex is a three‐dimensional polymer, [(en)Pb(μ3‐ONO)2Na(μ3‐ONO)2Na(μ‐O2ClO2)Na]n. The Pb and Na atoms have four‐ and eight‐coordinate geometry, respectively. The lone pair of electrons at the PbII atom is ‘stereochemically active’. 相似文献
992.
Jesús Castro Paulo Prez Lourido Antonio Sousa‐Pedrares Elena Labisbal Jos Piso Jos Arturo García‐Vzquez 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):m319-m322
The crystal structure of the title compound, [CoCl2(C6H12N2S)2], consists of monomer units of a CoII atom coordinated to two 1‐propylimidazolidine‐2‐thione ligands and to two chloride ions. The heterocyclic thione ligand is monodentate and coordinated to the metal through the thione S atom. The environment around the CoII atom is a slightly distorted tetrahedron. The Co—S bond lengths are 2.341 (2) and 2.330 (2) Å, and the Co—Cl bond lengths are 2.234 (2) and 2.238 (2) Å. The most important point of distortion is the S—Co—S bond angle of only 97.83 (8)°. Intramolecular classical hydrogen bonds are found between the chloride ions and the N—H groups. Additionally, intra‐ and intermolecular non‐classical hydrogen bonds are found. 相似文献
993.
L. N. Yang S. J. Qiu F. Xu L. X. Sun Z. B. Zhao J. G. Liang C. G. Song 《Journal of Thermal Analysis and Calorimetry》2007,89(3):875-879
The effects of Amoxicillin Sodium and Cefuroxime Sodium on the growth of E. coli DH5α were investigated by microcalorimetry. The metabolic power-time curves of E. coli DH5α growth were determined by using a TAM air isothermal microcalorimeter at 37°C. By evaluation of the obtained parameters,
such as growth rate constants (k), inhibitory ratio (I), the maximum heat power (P
m) and the time of the maximum heat power (t
m), one found that the inhibitory activity of Amoxicillin Sodium vs. E. coli DH5α is enhanced with the increasing of the Amoxicillin Sodium concentration, and the Cefuroxime Sodium has a stimulatory effect on the E. coli DH5α growth when the concentration is about 1 μg mL−1. The IC50 for the Amoxicillin Sodium and the Cefuroxime Sodium are 1.6 and 2.0 μg mL−1, respectively, it implicates that the E. coli DH5α is more sensitive to Amoxicillin Sodium than Cefuroxime Sodium. 相似文献
994.
An efficient and mild one‐pot synthesis of bis(oxazoline) (BOX) ligands is developed from reactions of dicarboxy dichlorides with β‐amino alcohols in the presence of 11.0 equiv. NEt3 followed by the addition of 3.6 equiv. methanesulfonyl chloride (MsCl). Nine different BOX ligands were prepared in excellent yields of ≥ 80%. Advantages of this improved synthesis are mild reaction conditions, short total reaction time of 9 h, and high isolated yields. 相似文献
995.
Semiconductor alpha-MoTe2 nanorods have been synthesized by annealing Te-seeded particles of an amorphous MoTe2 intermediate. This intermediate is prepared by a solution reaction between Mo(CO)6 and elemental Te in diphenylmethane. The as-synthesized products were characterized by structural, compositional, and morphological techniques of X-ray diffraction, selected area electron diffraction, selected area energy dispersive spectroscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. The results of the annealing process are MoTe2 nanorods with diameters of 50-200 nm and lengths ranging from 0.1 to 3.0 microm. Here, the rodlike structure of MoTe2 is reported for the first time, and added to the list as one kind of new morphology of MoTe2 nanomaterials. A mechanism for the formation of the nanorods is proposed. The sandwich-layered structure of Te-Mo-Te and the similarity in the structure between hexagonal alpha-MoTe2 and hexagonal Te are responsible for the formation of nanorods of MoTe2. 相似文献
996.
Gintaras Pivoriunas Ccilia Maichle‐Mssmer Simon Schwarz Joachim Strhle 《无机化学与普通化学杂志》2005,631(10):1743-1745
Synthesis and Crystal Structure of [(Ph3PAu)3NPPh3][PF6]2, a Gold(I) Phosphoraneiminato Complex The photolytic reaction of Ph3PAuN3 with Cr(CO)6 in THF yields the phosphoraneiminato complex [(Ph3PAu)3NPPh3]2+ in low yield as well as the cluster cation [(Ph3PAu)8]2+ as the main product. The phosphoraneiminato complex crystallizes from CH2Cl2 with [PF6]? ions as [(Ph3PAu)3NPPh3][PF6]2·CH2Cl2 in the triclinic space group with a = 1200.8(1), b = 1495.6(2), 2053.5(5), α = 86.97(2)°, β = 82.79(1)°, γ = 81.87(2)°, and Z = 2. The phosphoraneiminato ligand bridges through its N atom three Au atoms, which itself are connected to each other by weak aurophilic interactions. 相似文献
997.
HongWU ZhongJIANG SongWeiXU ShuFangHUANG 《中国化学快报》2003,14(4):423-425
CO2 is converted to nethanol through an enzymatic approach using formate dehydrogenase(FateDH),formaldehyde dehydrogenase(FaldDH)and alcohol dehydrogenase(ADH)coencapsulated in silica gel prepared by modified sol-gel process as catalysts,TEOS as precursor,NADH as an electron donor.The highest yield of methanol was up to 92.1% under 37℃,pH7.0 and 0.3Mpa. 相似文献
998.
Two three-dimensional (3D) malonate bridged networks, [Cu(mal)(DMF)](n) (1) and [[Cu(mal)(0.5pyz)].H(2)O](n) (2), have been synthesized in H(2)O-DMF solution. Compound 1 exhibits ferromagnetic ordering below 2.6 K (T(c)), and 2 displays a metamagnetic behavior below 3.2 K (T(N)). 相似文献
999.
Two novel coordination polymers of Co(II) with dicyanamide (dca) were obtained by the addition of ancillary ligands of pyrazine dioxide (pzdo) and 2-methyl pyrazine dioxide (mpdo) into the Co-dca binary system, respectively. Co[N(CN)(2)](2)(pzdo) (1) crystallizes in the orthorhombic space group of Pnnm (No. 58) with a = 9.4699(5) A, b = 14.9984(3) A, c = 7.4313(7) A, and Z = 4, while Co[N(CN)(2)](2)(mpdo) (2) is in the monoclinic space group C2 (No. 5) with a = 16.5391(4) A, b = 9.6065(2) A, c = 7.5001(2) A, beta = 105.779(1) degrees, and Z = 4. Both complexes contain similar two-dimensional triangular Co-dca layers, which offer rare examples of mixed 1,5-mu- and mu(3)-dca bridging coordination polymers with long-range ferromagnetic ordering below ca. 2.5 K. 相似文献
1000.
CompoundsformedfromCu ,AgandAuwithdithio lateligands ,suchasthedialkyldithiocarbamate (DTC) ,mercaptothiazoline (HMT)anddialkyldithiophosphates(DDP) ,haveplayedanimportantroleintechnology .1Cu(I) Sclustersalsohavebeenimplicatedinbiologyasan ti oxidants .2Thecuban… 相似文献