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991.
The fully chlorinated closo-dodecaborate salt Cs(2)[B(12)Cl(12)] was prepared in high yield from Cs(2)[B(12)H(12)] and SO(2)Cl(2) in acetonitrile at refluxing temperature. [Ph(3)C](2)[B(12)Cl(12)] was obtained by simple metathesis reactions. Catalytic hydrodefluorination of benzotrifluoride sp(3) C-F bonds was accomplished using [Ph(3)C](2)[B(12)Cl(12)] as a precatalyst and Et(3)SiH as a stoichiometric reagent. Full consumption of the sp(3) C-F bonds in p-FC(6)H(4)CF(3) and C(6)F(5)CF(3) with a turnover number up to 2000 was achieved. 相似文献
992.
The potential energy curves, permanent and transition dipole moments, and the static dipolar polarizability, of molecular ions composed of one alkali-metal atom and a strontium ion are determined with a quantum chemistry approach. The molecular ions are treated as effective two-electron systems and are treated using effective core potentials including core polarization, large gaussian basis sets, and full configuration interaction. In the perspective of upcoming experiments aiming at merging cold atom and cold ion traps, possible paths for radiative charge exchange, photoassociation of a cold lithium or rubidium atom and a strontium ion are discussed, as well as the formation of stable molecular ions. 相似文献
993.
Using the tricyano precursor (Bu(4)N)[(Tp)Cr(CN)(3)] (Bu(4)N(+) = tetrabutylammonium cation; Tp = tris(pyrazolyl)hydroborate), a pentanuclear heterometallic cluster [(Tp)(2)Cr(2)(CN)(6)Cu(3)(Me(3)tacn)(3)][(Tp)Cr(CN)(3)](ClO(4))(3)·5H(2)O (1, Me(3)tacn = N,N',N'-trimethyl-1,4,7-triazacyclononane), three tetranuclear heterometallic clusters [(Tp)(2)Cr(2)(CN)(6)Cu(2)(L(OEt))(2)]·2.5CH(3)CN (2, L(OEt) = [(Cp)Co(P(O)(OEt)(2))(3)], Cp = cyclopentadiene), [(Tp)(2)Cr(2)(CN)(6)Mn(2)(L(OEt))(2)]·4H(2)O (3), and [(Tp)(2)Cr(2)(CN)(6)Mn(2)(phen)(4)](ClO(4))(2) (4, phen = phenanthroline), and a one-dimensional (1D) chain polymer [(Tp)(2)Cr(2)(CN)(6)Mn(bpy)](n) (5, bpy = 2,2'-bipyridine) have been synthesized and structurally characterized. Complex 1 shows a trigonal bipyramidal geometry in which [(Tp)Cr(CN)(3)](-) units occupy the apical positions and are linked through cyanide to [Cu(Me(3)tacn)](2+) units situated in the equatorial plane. Complexes 2-4 show similar square structures, where Cr(III) and M(II) (M = Cu(II) or Mn(II)) ions are alternatively located on the rectangle corners. Complex 5 consists of a 4,2-ribbon-like bimetallic chain. Ferromagnetic interactions between Cr(III) and Cu(II) ions bridged by cyanides are observed in complexes 1 and 2. Antiferromagnetic interactions are presented between Cr(III) and Mn(II) ions bridged by cyanides in complexes 3-5. Complex 5 shows metamagnetic behavior with a critical field of about 22.5 kOe at 1.8 K. 相似文献
994.
Hierarchical nanotubular rutile titania material was fabricated by facile flame burning of ultrathin titania gel film coated cellulose nanofibres of commercial cellulose substance (filter paper), which possesses efficient photocatalytic performance for degradation of organic dye (methylene blue) under ultraviolet irradiation. 相似文献
995.
Metal-organic frameworks MIL-53, MIL-100 and MIL-101 demonstrate efficient enrichment of peptides with simultaneous exclusion of proteins from complex biological samples. 相似文献
996.
Mesoporous Co3O4 monolayer hollow-sphere array as electrochemical pseudocapacitor material 总被引:1,自引:0,他引:1
Xia XH Tu JP Wang XL Gu CD Zhao XB 《Chemical communications (Cambridge, England)》2011,47(20):5786-5788
A Co(3)O(4) monolayer hollow-sphere array with mesoporous walls exhibits high pseudocapacitances of 358 F g(-1) at 2 A g(-1) and 305 F g(-1) at 40 A g(-1), as well as excellent cycling stability for application as pseudocapacitors. 相似文献
997.
Dong S Chen X Zhang K Gu L Zhang L Zhou X Li L Liu Z Han P Xu H Yao J Zhang C Zhang X Shang C Cui G Chen L 《Chemical communications (Cambridge, England)》2011,47(40):11291-11293
Molybdenum nitride/nitrogen-doped graphene nanosheets (MoN/NGS) are synthesized and used as an alternative O(2) electrode for Li-O(2) batteries. In comparison with electrocatalysts proposed previously, this hybrid cathode exhibits a high discharge potential (around 3.1 V) and a considerable specific capacity (1490 mA h g(-1), based on carbon + electrocatalyst). 相似文献
998.
A novel and highly sensitive immunoassay method based on surface enhanced Raman spectroscopy (SERS) and magnetic particles has been developed. This method exhibits great potential application in bio-separation and immunoassay. 相似文献
999.
Choi J Jin J Jung IG Kim JM Kim HJ Son SU 《Chemical communications (Cambridge, England)》2011,47(18):5241-5243
Through a solution approach, SnSe(2) nanoplate-graphene composites were prepared and applied as anode materials in lithium ion batteries, showing promising storage performance superior to SnSe(2) nanoplates or graphene alone. 相似文献
1000.
Zhang CP Wang ZL Chen QY Zhang CT Gu YC Xiao JC 《Chemical communications (Cambridge, England)》2011,47(23):6632-6634
The CF(3) radical was generated from the reaction of S-(trifluoromethyl)diphenylsulfonium triflate with Na(2)S(2)O(4) or HOCH(2)SO(2)Na under suitable conditions without further reduction. Based on this, a method for the synthesis of α-trifluoromethylated ketones has been successfully developed. 相似文献