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991.
Anion photoelectron spectroscopy and theoretical calculations are combined to probe the structures and chemical bonding of two boron-rich oxide clusters, B(5)O(3)(-) and B(6)O(3)(-), which are shown to be appropriately formulated as B(2)(BO)(3)(-) and B(3)(BO)(3)(-), respectively. The anion clusters are found to each possess a bridging η(2)-BO group, as well as two terminal BO groups and are analogs of B(2)H(3)(-) and B(3)H(3)(-). This finding advances the boronyl chemistry and helps establish the isolobal analogy between boron-rich oxide clusters and boranes. 相似文献
992.
Chen Y Hu S Liu W Chen X Wu L Wang X Liu P Li Z 《Dalton transactions (Cambridge, England : 2003)》2011,40(11):2607-2613
Cubic ZnIn(2)S(4) nanoparticles and hexagonal ZnIn(2)S(4) flower-like microspheres were controlled synthesized via a facile hydrothermal method by simply changing the metal precursors. The as-prepared samples were characterized by XRD, SEM, TEM and UV-vis DRS. It was found that the metal precursors influenced the final ZnIn(2)S(4) polymorphs, i.e., metal nitrates led to the formation of cubic ZnIn(2)S(4), while metal chlorides resulted in the formation of the hexagonal phase. The formation processes of the cubic ZnIn(2)S(4) nanoparticles and hexagonal ZnIn(2)S(4) flower-like microspheres were investigated and the mechanism of the phase formation was proposed. Although both cubic and hexagonal ZnIn(2)S(4) polymorphs exhibited photocatalytic activity for the degradation of methyl orange (MO) under visible light irradiation, the photocatalytic performances over cubic and hexagonal ZnIn(2)S(4) were different. 相似文献
993.
Zhai X Yu M Cheng Z Hou Z Ma P Yang D Kang X Dai Y Wang D Lin J 《Dalton transactions (Cambridge, England : 2003)》2011,40(48):12818-12825
Rattle-type hollow nanocapsules are among of the most promising candidates as drug carriers owing to their huge inner space and multifunctional material combination. In this paper, rattle-type hollow CaWO(4):Tb(3+)@SiO(2) nanocapsules with a diameter of 100-110 nm and a wall thickness around 10 nm were fabricated. The hollow silica nanospheres were used as nano-reactors and the luminescent core of CaWO(4):Tb(3+) was post-filled into the nano-reactors by a vacuum nano-casting route combined with a Pechini-type sol-gel method. Subsequently, doxorubicin hydrochloride (DOX), a model of an anti-cancer drug, is loaded into the CaWO(4):Tb(3+)@SiO(2) nanocapsules and their cell cytotoxicity, cancer cell uptake and drug release behavior are investigated in vitro. The prepared multifunctional inorganic nanocapsules show a loading capacity for DOX as high as 124 mg g(-1) and sustained-release properties. The release profile of the drug from DOX-loaded nanocapsules can last over five days. Besides, the blank CaWO(4):Tb(3+)@SiO(2) shows very low cytotoxicity against cancer cell lines (HeLa cell) while the DOX-loaded nanocapsules exhibit relatively high efficiency for killing of HeLa cells. The rapid cancer cell uptake process is observed by confocal laser scanning microscopy. The results indicate that a rattle-type hollow CaWO(4):Tb(3+)@SiO(2) nanocapsule has the potential to be used as drug carrier in therapy. Moreover, it is possible to extend the synthetic strategy in this study to other rattle-type multifunctional composites to meet various demands. 相似文献
994.
Xu X Li X Lin P Chen T Yuan R Ding Z Wu L Wang X Li Z 《Chemical communications (Cambridge, England)》2011,47(9):2538-2540
Sequential impregnations of metal ions and titanium tetraisopropoxide (TTIP) into activated carbon fibers (ACF) followed by a solvothermal treatment has been found to be a general method in the preparations of homogeneous and composition-tunable hybrid TiO(2) hierarchical nanocomposite fibers like WO(3)/TiO(2), Fe(2)O(3)/TiO(2) and SnO(2)/TiO(2). 相似文献
995.
Lee JJ Lee SC Zhai D Ahn YH Yeo HY Tan YL Chang YT 《Chemical communications (Cambridge, England)》2011,47(15):4508-4510
A bodipy probe was developed for site-specific labeling of tagged proteins inside live cells which displays a large spectral change upon covalent coupling to the designed peptide that contains two pairs of Arg-Cys. 相似文献
996.
Zou C Zhang L Zhai L Lin D Gao J Li Q Yang Y Chen X Huang S 《Chemical communications (Cambridge, England)》2011,47(18):5256-5258
We have demonstrated that quaternary Cu(x)In(x)Zn(2(1-x))S(2) nanobelts could be synthesized through a facile solution-based method. The composition and band gap of quaternary nanobelts can be tuned within the broad range by changing the relative ratio of precursors. The growth mechanism of quaternary nanobelts was deduced to be catalyst-assisted growth. 相似文献
997.
Background
The importance of the isatinic quinolyl hydrazones arises from incorporating the quinoline ring with the indole ring. Quinoline ring has therapeutic and biological activities whereas, the indole ring occurs in Jasmine flowers and Orange blossoms. As a ligand, the isatin moiety is potentially ambidentate and can coordinate the metal ions either through its lactam or lactim forms. In a previous study, the ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions has been studied. As continuation of our interest, the present study is planned to check the ligational behavior of an isatinic quinolyl hydrazone.Results
New homo- and heteroleptic copper(II)- complexes were obtained from the reaction of an isatinic quinolyl hydrazone (HL) with several copper(II)- salts viz. Clˉ, Brˉ, NO3ˉ, ClO4 -, SO4 2- and AcO-. The obtained complexes have Oh, Td and D4h- symmetry and fulfill the strong coordinating ability of Clˉ, Brˉ, NO3ˉ and SO4 2- anions. Depending on the type of the anion, the ligand coordinates the copper(II)- ions either through its lactam (NO3ˉ and ClO4 -) or lactim (the others) forms.Conclusion
The effect of anion for the same metal ion is obvious from either the geometry of the isolated complexes (Oh, Td and D4h) or the various modes of bonding. Also, the obtained complexes fulfill the strong coordinating ability of Clˉ, Brˉ, NO3ˉ and SO4 2- anions in consistency with the donor ability of the anions. In case of copper(II)- acetate, a unique homoleptic complex (5) was obtained in which the AcO- anion acts as a base enough to quantitatively deprotonate the hydrazone. The isatinic hydrazone uses its lactim form in most complexes. 相似文献998.
999.
Zeolite A and A + X mixtures were prepared from coal-fly ash procured from China by using an alkali fusion method. X-ray diffraction
showed that both the materials were crystalline and reproducible. Scanning Microscopy revealed that pure zeolite A particles
have cubic morphology while the mixture shows intergrowth of cubic and pyramidal crystals. The surface area for A + X mixture
was around 330 m2/g which is higher than zeolite A, however, lower than typical X zeolite. CO2 and N2 adsorption isotherms were measured and the data was fitted by the Dual Site Langmuir equation. These zeolites were then tested
for CO2 capture at different temperatures in a process with a nine step cycle. When compared with 13X zeolites at higher temperature
(∼90 °C), both the zeolite A + X mixture and zeolite A prepared from fly ash showed better performance in CO2 capture from flue gas because they have higher selectivity of CO2 over N2. 相似文献
1000.
Shi J Ye J Zhou Z Li M Guo L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(28):7858-7867
Cubic perovskite structure photocatalysts of Na(0.5)La(0.5)TiO(3) and (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08) solid solution that consisted of well-defined single-crystal nanocubes were successfully prepared by means of facile and surfactant-free hydrothermal reactions for the first time. The results from different instrumental characterizations and theoretical calculations consistently confirmed the formation of nanocubic single-crystal solid solution of (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08), and clearly revealed the modification of its physicochemical properties compared with those of Na(0.5)La(0.5)TiO(3). In particular, the effective narrowing of the bandgap (from 3.19 to 2.25 eV) by Cr(3+) in the solid solution made it possible to utilize visible light. The solid-solution configuration maintained the charge balance to preserve the valence of Cr(3+) rather than Cr(6+), and accommodated Cr(3+) with high content to form new energy bands instead of localized impurity levels. The hydrothermal preparation strategy ensured the formation of single crystals with high purity, few defects, and regulated morphology; it also guaranteed the valences of Ti(4+) and Cr(3+) in the solid solution. Consequently, the recombination of photogenerated carriers could be effectively suppressed to benefit photocatalytic H(2) evolution. (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08) nanocubic single-crystal solid solution showed stable photocatalytic activity, and thus was proved to be a promising candidate for visible-light-driven photocatalytic H(2) evolution. 相似文献