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991.
Treatment of the appropriate lithium or sodium 2,4-N,N'-disubstituted 1,3,5-triazapentadienate [RNC(R')NC(R')N(SiMe(3))M](2) (R = Ph, 2,6-(i)Pr(2)-C(6)H(3)(Dipp) or SiMe(3); R' = NMe(2) or 1-piperidino; M = Li or Na) with one or half equivalent portion of MgBr(2)(THF)(2) in Et(2)O under mild conditions furnishes in good yield the first structurally characterized molecular magnesium 2,4-N,N'-disubstituted 1,3,5-triazapentadienates [DippNC(NMe(2))NC(NMe(2))N(SiMe(3))MgBr](2) (1), [{RNC(R')NC(R')N(SiMe(3))}(2)Mg] (R = Ph, R' = NMe(2) 2; R = Ph, R' = 1-piperidino 3; R = SiMe(3), R' = 1-piperidino 4). The solid-state structure of 1 is dimeric and those of 2, 3, and 4 are monomeric. The ligand backbone NCNCN in 1 adopts a W-shaped configuration, while in 2, 3 and 4 adopts a U-shaped configuration. 相似文献
992.
Wen CZ Hu QH Guo YN Gong XQ Qiao SZ Yang HG 《Chemical communications (Cambridge, England)》2011,47(21):6138-6140
Single-crystalline TiOF(2) crystals with cubical morphology were prepared via a facile solvothermal method and their transformation to anatase TiO(2) under different calcination conditions such as pure argon, moist argon and pure hydrogen sulfide (H(2)S) was explored by using XRD/Raman/UV-Vis/SEM/TEM/SAED. The non-metal sulfur doping was successfully fulfilled and the doped TiO(2) microcubes showed the best photocatalytic H(2) evolution property. 相似文献
993.
Gong HY Rambo BM Cho W Lynch VM Oh M Sessler JL 《Chemical communications (Cambridge, England)》2011,47(21):5973-5975
A three-dimensional extended, metal-organic rotaxane framework (MORF) that incorporates encircled "struts" has been synthesized through a one-pot self-assembly process involving a macrocyclic tetraimidazolium "molecular box", naphthalene dicaboxylate dianion, and Zn(II) cations. The present system represents progress towards controlling the features of three-dimensional metal-organic frameworks. 相似文献
994.
Cheng G Zhang JL Liu YL Sun DH Ni JZ 《Chemical communications (Cambridge, England)》2011,47(20):5732-5734
Fe(3)O(4)@SiO(2)@CeO(2) microspheres with magnetic core and mesoporous shell were synthesized, and the multifunctional materials were utilized to capture phosphopeptides and catalyze the dephosphorylation simultaneously, thereby labeling the phosphopeptides for rapid identification. 相似文献
995.
A highly enantioselective Friedl?nder condensation has been established by using chiral Br?nsted acids in combination with achiral amines to give quinolines in high yields (up to 99%) and with excellent enantioselectivities (up to 95%). 相似文献
996.
Chiral organophosphine-catalyzed enantioselective Rauhut-Currier reaction has been disclosed for the first time. With L-valine-derived phosphinothiourea, the intramolecular Rauhut-Currier reaction of bis(enones) was achieved in good yields (up to 99%) with excellent enantioselectivities (up to 99.4% ee). 相似文献
997.
Zhang X Lu X Shen Y Han J Yuan L Gong L Xu Z Bai X Wei M Tong Y Gao Y Chen J Zhou J Wang ZL 《Chemical communications (Cambridge, England)》2011,47(20):5804-5806
Three-dimensional (3D) WO(3) nanostructures were grown on carbon paper by a catalyst-free high temperature reactive vapor deposition process, which exhibit a good photoelectrochemical property and visible light driven photocatalytic performance. 相似文献
998.
A series of N-methyl-4-phenoxypicolinamide derivatives were synthesized and evaluated in vitro for their cytotoxic activity against A549, H460 and HT29 cell lines. Pharmacological data indicated that some of the target compounds possessed marked antiproliferative activity, superior to that of the reference drug sorafenib. As the most promising compound, 8e exhibited potent cytotoxicity with the IC(50) value of 3.6, 1.7 and 3.0 μM against A549, H460 and HT-29 cell lines, respectively. 相似文献
999.
Chen-Zhong Yao Hui-Xuan Ma Xi-Sheng Zhang Li-Xin Meng Li-Ping Zhao Ling Tai Yu-Chun Wang Qiao-Juan Gong Ye-Xiang Tong 《Journal of Solid State Electrochemistry》2011,15(6):1193-1199
Magnetic dendrites of Co
x
Pb1−x
were fabricated through potentiostatic electrochemical deposition on Cu substrates in boric acid solution at room temperature.
The as-deposited dendrites were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron
microscopy (TEM), electrodeposition (ED), and energy dispersive X-ray spectroscopy (EDS). SEM results indicate that the Co
x
Pb1−x
dendrites are highly symmetrical in structures. The diameters of the branches are about 50 ~ 200 nm, and the backbones are
continuous with lengths up to about 10 μm. XRD patterns show that the as-deposited dendrites are solid solutions. The annealing
treatment can result in the recrystallization of these metastable alloys into two separate phases. TEM, ED, and EDS results
also reveal that the backbones and the branches of the dendrites are composed of different amounts of cobalt. Magnetic measurements
confirm that the as-deposited Co
x
Pb1−x
dendrites have a softly ferromagnetic behavior, and a small coercive force (about 80 Oe). Also the saturation magnetizations
of the Co
x
Pb1−x
dendrites decrease rapidly with the temperature increasing. 相似文献
1000.
Manoj Yadav Wenquan Gong Allan J. Jacobson 《Journal of Solid State Electrochemistry》2011,15(2):293-301
Oxygen gas can be electrochemically separated from ambient air with very high purity and compressed by using a solid-electrolyte
ion-transport membrane. An electrolyte with high ionic conductivity such as gadolinium-doped ceria (CGO) and mixed conducting
electrodes are used to construct the electrochemical cell. To achieve high oxygen flux, the electrodes must exhibit very fast
electrode kinetics. Here, we report the performances of mixed conducting PrBaCo2O5 + x
and NdBaCo2O5 + x
electrodes in oxygen separation in a planar CGO electrolyte-supported cell. The properties of the electrode materials were
evaluated using potentiostatic and potentiodynamic measurements and alternating current impedance spectroscopy. The oxygen
flux was also measured using gas chromatography to confirm the absence of gas leaks. The electrodes demonstrated very low
polarization resistances as a result of very high cathodic and anodic reaction rates at temperatures of 600–800 °C. High oxygen
gas flow rates were observed on applying potentials up to 1 V with an almost linear relationship between the applied potential
and the molar flow rate of oxygen gas. 相似文献