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91.
Ponomarova VV Komarchuk VV Boldog I Chernega AN Sieler J Domasevitch KV 《Chemical communications (Cambridge, England)》2002,(5):436-437
Cross-linking of corrugated square grid coordination layers by anionic bridging groups generates five-connected coordination networks; the 3D topologies of mixed-anion cobalt(II) and nickel(II) complexes with a tetramethyl-substituted 4,4'-bipyrazolyl ligand are supported by mu-SO4(2-) functions and exist as neutral or cationic five-connected arrays involving additional terminal (NCS-) or non-coordinated (NO3-, ClO4-) groups. 相似文献
92.
We report the first calculations carried out with a periodic boundary condition code capable of examining hybrid density-functional theory (DFT) for f-element solids. We apply it to the electronic structure of the traditional Mott insulator UO2, and find that it correctly yields an antiferromagnetic insulator as opposed to the ferromagnetic metal predicted by the local spin density and generalized gradient approximations. The gap, density of states, and optimum lattice constant are all in good agreement with experiment. We stress that this results from the functional and the variational principle alone. We compare our results with the more traditional approximations. 相似文献
93.
We describe the topological structure and the underlying organization principles of the directories created by users of a computer cluster. Users create trees with a scale-free degree distribution whose properties are reproduced by a growth and preferential attachment mechanism with a single parameter. The degree distribution has a nonuniversal exponent associated with different values of the parameter. However, the distribution of branch sizes has a universal exponent analytically obtained from the model. 相似文献
94.
Konstantinova LS Rakitin OA Rees CW Souvorova LI Golovanov DG Lyssenko KA 《Organic letters》2003,5(11):1939-1942
[reaction: see text] In a remarkable cascade reaction, triethylamine is converted into the thienopentathiepin 2a and the heptathiocane 3a by a preequilibrated solution of disulfur dichloride and DABCO in chloroform. 相似文献
95.
We give examples of analytic circle maps with singularities of break type with the same rotation number and the same size of the break for which no conjugacy is Lipschitz continuous. In the second part of the paper, we discuss a class of rotation numbers for which a conjugacy is C1-smooth, although the numbers can be strongly non-Diophantine (Liouville). For the rotation numbers in this class, we construct examples of analytic circle maps with breaks, for which the conjugacy is not C1+α smooth, for any α>0. 相似文献
96.
Evgen V. Govor Andrey B. Lysenko Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(5):m201-m204
New coordination compounds with the 4,4′‐bi‐1,2,4‐triazole ligand (btr), namely tetraaqua‐2κ4O‐di‐μ2‐4,4′‐bi‐1,2,4‐triazole‐1:2κ2N1:N1′;2:3κ2N1:N1′‐hexachlorido‐1κ3Cl,3κ3Cl‐trizinc(II), [Zn3Cl6(C4H4N6)2(H2O)4], (I), and poly[cadmium(II)‐μ2‐4,4′‐bi‐1,2,4‐triazole‐κ2N1:N2‐di‐μ2‐chlorido], [CdCl2(C4H4N6)]n, (II), reveal an unprecedented molecular zwitterionic structure for (I) and a polymeric two‐dimensional layer structure for (II). Differences between these products, which involve the formation of either charge‐separated chlorometallate/aquametal fragments or complementary organic and inorganic bridges, are attributable to the hardness–softness characters of the metal cations. In (I), two N1,N1′‐bidentate btr molecules connect one [Zn(H2O)4]2+ cation and two [ZnCl3]− anions into a linear trizinc motif (the Zn atom of the cation occupies a centre of inversion in an N2O4 coordination octahedron, whereas the Zn atom of the anion possesses a distorted tetrahedral Cl3N environment). In (II), the distorted vertex‐sharing CdCl4N2 octahedra are linked into binuclear [Cd2(μ2‐Cl)(μ2‐btr)2]3+ fragments by unprecedented N1:N2‐bidentate btr double bridges and bridging chloride ligands, while the additional chloride anions are also bridging, providing further propagation of the fragments into a two‐dimensional network [Cd—Cl = 2.5869 (2)–2.6248 (7) Å]. 相似文献
97.
Konstantin M Dyakonov 《Advances in Mathematics》2004,187(1):146-172
We discuss the implication , where f is a holomorphic function (resp., a quasiconformal mapping) on a domain (resp., ) and Λω(G) is the Lipschitz space associated with a majorant ω. 相似文献
98.
Ma LL Tam JO Willsey BW Rigdon D Ramesh R Sokolov K Johnston KP 《Langmuir : the ACS journal of surfaces and colloids》2011,27(12):7681-7690
The ability of smaller than 100 nm antibody (Ab) nanoparticle conjugates to target and modulate the biology of specific cell types may enable major advancements in cellular imaging and therapy in cancer. A key challenge is to load a high degree of targeting, imaging, and therapeutic functionality into small, yet stable particles. A versatile method called thin autocatalytic growth on substrate (TAGs) has been developed in our previous study to form ultrathin and asymmetric gold coatings on iron oxide nanocluster cores producing exceptional near-infrared (NIR) absorbance. AlexaFluor 488 labeled Abs were used to correlate the number of Abs conjugated to iron oxide/gold nanoclusters (nanoroses) with the hydrodynamic size. A transition from submonolayer to multilayer aggregates of Abs on the nanorose surface was observed for 54 Abs and an overall particle diameter of ~60-65 nm. The hydrodynamic diameter indicated coverage of a monolayer of 54 Abs, in agreement with the prediction of a geometric model, by assuming a circular footprint of 16.9 nm diameter per Ab molecule. The targeting efficacy of nanoclusters conjugated with monoclonal Abs specific for epidermal growth factor receptor (EGFR) was evaluated in A431 cancer cells using dark field microscopy and atomic absorbance spectrometry (AAS) analysis. Intense NIR scattering was achieved from both high uptake of nanoclusters in cells and high intrinsic NIR absorbance of individual nanoclusters. Dual mode imaging with dark field reflectance microscopy and fluorescence microscopy indicates the Abs remained attached to the Au surfaces upon the uptake by the cancer cells. The ability to load intense multifunctionality, specifically strong NIR absorbance, conjugation of an Ab monolayer in addition to a strong r2 MRI contrast that was previously demonstrated in a total particle size of only 63 nm, is an important step forward in development of theranostic agents for combined molecular specific imaging and therapy. 相似文献
99.
Lukyanov KA 《Chemistry & biology》2011,18(10):1202-1204
Photoactivatable fluorescent proteins are now widely used for cell and protein tracking and super-resolution optical imaging. In this issue, Adam et?al. (2011) report a general approach to introduce photochromism into green-to-red photoconvertible proteins and describe new photoactivatable protein with a complex four-state flasher-like behavior and advanced characteristics. 相似文献
100.