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971.
Yun-Yin Niu Ben-Lai Wu Qing-Li Wang Xiao-Ling Guo Hong-Yun Zhang Hong-Wei Hou Yi Han Ling-Fang Wang 《Inorganica chimica acta》2009,362(2):556-2112
Three new coordination polymers based on IB metal thiocyanates, [CuII(NCS)2(DMSO)4(meso-dpb)]n (1), (2), [CuI(NCS)(pia)]n (3) (dpb = 2,3-di(4-pyridyl)-2,3-butanediol, bpp = 1,3-bis(4-pyridyl)propane, pia = N,N′-(1,2-phenylene)diisonicotinamide), have been synthesized by the pre-assembly method and characterized by X-ray crystallography. In 1, CuII cations are bridged by meso-dpb ligands to form a one-dimensional (1D) linear chain. Compound 2 consists of 2D undulated layers of (4, 4) topology that show twofold parallel interpenetration. In the case of 3, the MI center adopts tetrahedral coordination geometry and the 2D networks are formed by organic ligand with “folding ruler-shaped” NCS−-M chains. The thermal properties of 1-3 were also investigated. 相似文献
972.
A facile synthetic procedure has been used to prepare one five-coordinate and four six-coordinate copper(II) complexes of 4′-chloro-2,2′:6′,2″-terpyridine (tpyCl) ligand with different counterions (, , , , and ) in high yields. They are formulated as [Cu(tpyCl-κ3N,N′,N′′)(SO4-κO)(H2O-κO)] · 2H2O (1), trans-[Cu(tpyCl-κ3N,N′,N″)(NO3-κO)2(H2O-κO)] (2), [Cu(tpyCl-κ3N,N′,N″)2](BF4)2 (3), [Cu(tpyCl-κ3N,N′,N″)2](PF6)2 (4) and [Cu(tpyCl-κ3N,N′,N″)2](ClO4)2 (5) and versatile interactions in supramolecular level including coordinative bonding, O-H?O, O-H?Cl, C-H?F, and C-H?Cl hydrogen bonding, π-π stacking play essential roles in forming different frameworks of 1-5. It is concluded that the difference of coordination abilities of the counterions used and the experimental conditions codominate the resulting complexes with 1:1 or 1:2 ratio of metal and ligand. 相似文献
973.
Ostracode shell chemistry is a powerful tool for recording changes of certain dissolved ions in their environment. Such data
are commonly interpreted in terms of change in temperature and salinity, which are then used to offer insights into paleohydrology
and from that paleoclimate. In particular, the changes in Sr/Cashell are believed to reflect changes in salinity, and the changes in Mg/Cashell to reflect both salinity and water temperature. However, the established application of this proxy too often ignores the
complexities involved in the chemical changes accompanying solute evolution, hydrologic change, physical chemistry, and the
autoecology and biology of ostracodes. Chemical changes occur: (1) in the dissolved Mg/Ca and Sr/Ca ratios during solute evolution,
(2) as a consequence of multiple sources of water, but especially ground and surface water interchange as well as evaporation,
(3) as a consequence of different dissolved cation–anion pair formation at various concentrations, and (4) because of bio/ecologic
effects, including seasonality of molting and taxa-specific ionic regulation capabilities. We suggest that changes in shell
chemistry in a stratigraphic sequence tell us when changes occurred in the solutes, but cannot identify what caused those
change(s) in the chemical environment. Inclusion of information from other paleoenvironmental and paleoclimatic proxies that
co-occur with ostracode shells may help to limit the choices amongst possible causes.
相似文献
Emi ItoEmail: |
974.
The title complexes are synthesized by the reaction of an unusual ligand of [K2P2W18(UO2)2O68]12− (1) and [KAs2W18(UO2)2O68]13− (2) with divalent metal ions of CoII, CuII, MnII, NiII and ZnII in 1:2 mole ratio and are characterized by elemental analysis, IR, 31P NMR, UV-Vis spectroscopy, TGA, and single crystal structure analysis. Crystals of [P2W18(UO2)2{(H2O)3Co}2O68]10− (1a) and [As2W18(UO2)2{(H2O)3Cu}2O68]10− (2b) are orthorhombic space group Cmca. Both 1a and 2b have structures in which two [M(H2O)3] (M = CoII, CuII) and two UO2 groups are sandwiched between two symmetry equivalent (XW9) (X = P, As) units in a virtual Ci symmetry. In solution, 1a and [P2W18(UO2)2{(H2O)3Zn}2O68]10− (1d) give two-line P NMR spectra that are consistent with a Cs symmetry structures so, are not consistent with the solid-state structures. The sodium salts of them give one-line P NMR spectra and are consistent with the Ci symmetry of solid-state structures. The uranium atoms have pentagonal-bipyramidal coordination, achieved by three equatorial bonds to the one XW9 and two bonds to the other. The M atoms have octahedral or square pyramidal coordination, but only one bond to the one XW9 and one bond to the other. 相似文献
975.
Sandra S. Rodrigues José A. Fernandes Maria M. Marques 《Inorganica chimica acta》2009,362(4):1275-1281
[M(P3C2tBu2)(CO)3I] (M = Mo, 1, W, 2) have been synthesised and reacted with PCl5 for oxidation study purposes. Compounds Ti(P3C2tBu2)(Ind)Cl2], 3, and [Zr(P3C2tBu2)(Cp)Cl2], 4, were detected spectroscopically, but showed to be too unstable to be isolated. A Ti(IV) complex, [Ti(P3C2tBu2)Cl3], 5, has been formed from the reaction of [TiCl4] with the base-free ligand K(P3C2tBu2), while the Ti(III) species, [Ti(P3C2tBu2) Cl2(THF)], 6, was prepared from [TiCl3(THF)3]. Compounds 5 and 6 were studied as ethylene catalyst precursors after activation with MAO. In the studied conditions, complex 5 is the most active one with an activity of 2.2 × 105 g(molTi [E] h)−1, one order of magnitude higher than compound 6. The produced polymer is linear polyethylene. 相似文献
976.
The formation reactions of hydrophobic metal complexes of divalent typical element and transition metal ions with a novel chelating ligand containing N and O donor atoms, 4,5-bis(diphenylphosphinoyl)-1,2,3-triazole (LTH), were investigated by the liquid-liquid distribution method carried out on metal ions between chloroform and aqueous solutions. The liquid-liquid distribution reaction formulae of metal ions via the formation of hydrophobic metal complexes were revealed, along with their equilibrium constants. Three types of hydrophobic mononuclear and binuclear metal complexes distributed into chloroform solutions were found, namely, ML2 (M = Mg2+, Zn2+, Pb2+; L = LT−), ML2(HL) (M = Cd2+, Mn2+), and M2L3(OH) (M = Co2+, Ni2+, Cu2+). Linear free energy relationships were found between the equilibrium constants of the liquid-liquid distribution reactions and the stability constants of 1:1 complexes consisting of a divalent metal ion and a glycinate. These relationships suggest the chelate formation of N,O-coordination with a heterocyclic five-membered ring in the metal complexes with LTH. 相似文献
977.
The perchlorate M(II) (M = Cu, Ni, Co) complexes with the diethyl (pyridin-4-ylmethyl)phosphate (4-pmOpe) ligand of the composition [M(4-pmOpe)2 (H2O)2](ClO4)2 (M = Ni, Co) and [Cu(4-pmOpe)2(ClO4)2] were prepared and studied. The ligand contains two donor atoms, i.e. pyridine nitrogen and phosphoryl oxygen atoms. In particular, the crystal structure of [Cu(4-pmOpe)2(ClO4)2] was determined by the X-ray method. Its structure consists of a one-dimensional polymeric chain in which copper(II) ions are N,O-bridged by two 4-pmOpe organic ligands in a trans arrangement. Two perchlorate ions occupy the fifth and the sixth coordination sites. The Cu?Cu distance is 9.180 Å. The crystal packing is determined by the weak intermolecular C-H?O hydrogen contacts. The coordination compounds were identified and characterized by elemental analysis, spectroscopic and magnetic studies. Spectroscopic and magnetic results of the copper(II) compound are presented in the light of the crystal structure. The magnetic data indicate very weak intra- and interchain magnetic exchange interactions (J’ = −0.43 and zJ’ = 0.29 cm−1, respectively). The spectroscopic and magnetic properties of the Co(II) and Ni(II) complexes indicate octahedral and polymeric structure of both compounds in which 4-pmOpe ligand also acts as N,O-bridge between metal ions. 相似文献
978.
Diamido-supported rare earth metal amides with the general formula {(CH2SiMe2)[(2,6-iPr2C6H3)N]2}LnN(SiMe3)2(THF) [(Ln = Yb(1), Y(2), Dy(3), Sm (4), Nd (5)] were found to be highly efficient catalysts for the guanylation of both aromatic and heterocyclic amines under mild conditions. It is found that these catalysts are compatible with a wide range of substituents such as iPr, Me, and MeO having electron-donating property and substituents such as Cl, Br, and O2N having electron-withdrawing property on the aromatic rings of the aromatic or the heterocyclic amines. The methodology has also the advantages of easy preparation of the catalysts, quick conversion of the substrates to products, mild reaction conditions, and low catalyst loading. 相似文献
979.
Alma Balestrazzi Silvia Botti Samantha Zelasco Stefania Biondi Cinzia Franchin Paolo Calligari Milvia Racchi Adelaide Turchi Guido Lingua Graziella Berta Daniela Carbonera 《Plant cell reports》2009,28(8):1179-1192
Marker-free transgenic white poplar (Populus alba L., cv ‘Villafranca’) plants, expressing the PsMT
A1
gene from Pisum sativum for a metallothionein-like protein, were produced by Agrobacterium tumefaciens-mediated transformation. The 35SCaMV-PsMT
A1
-NosT cassette was inserted into the ipt-type vector pMAT22. The occurrence of the abnormal ipt-shooty phenotype allowed the visual selection of transformants, while the yeast site-specific recombination R/RS system was
responsible for the excision of the undesired vector sequences with the consequent recovery of normal marker-free transgenic
plants. Molecular analyses confirmed the presence of the 35SCaMV-PsMT
A1
-NosT cassette and transgene expression. Five selected lines were further characterized, revealing the ability to withstand
heavy metal toxicity. They survived 0.1 mM CuCl2, a concentration which strongly affected the nontransgenic plants. Moreover, root development was only slightly affected
by the ectopic expression of the transgene. Reactive oxygen species were accumulated to a lower extent in leaf tissues of
multi-auto-transformation (MAT)-PsMTA1 plants exposed to copper and zinc, compared to control plants. Tolerance to photo-oxidative stress induced by paraquat was
another distinctive feature of the MAT-PsMTA1 lines. Finally, low levels of DNA damage were detected by quantifying the amounts of 8-hydroxy-2′-deoxyguanosine in leaf
tissues of the transgenic plants exposed to copper. 相似文献
980.
Fernando Fornes Rosana García-de-la-FuenteRosa M. Belda Manuel Abad 《Bioresource technology》2009,100(17):3982-3990
The effects of ‘alperujo’ compost on trace element availability and on microbial activity of two contaminated soils, a calcareous soil (S1) with high contents of Pb and Zn, and an acidic soil (S2) with a substantial amount of Al, As, Pb and Zn, were assessed. Additionally, the growth and capacity for contaminant phytoextraction of five Brassica species were studied. Compost amendment did not affect S1, but in S2 it increased soil pH, thus reducing Al and Zn bioavailability and toxicity. Compost application also increased microbial population and bioactivity in both soils. Brassica plants did not survive in S2, yet they thrived in S1. When compost was applied to S2, Brassica carinata, Brassica napus and Brassica oleracea grew adequately. Considering both the capacity to accumulate trace elements in the shoot and the ability to grow in the contaminated soils tested, the most efficient phytoextractors were Brassica juncea in S1 (particularly for Zn) and Brassica oleracea in S2 (for Al, As, Pb and Zn). 相似文献