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991.
Yun TK Park SS Kim D Shim JH Bae JY Huh S Won YS 《Dalton transactions (Cambridge, England : 2003)》2012,41(4):1284-1288
The effect of the rutile content on the photovoltaic performance of dye-sensitized solar cells (DSSCs) composed of mixed-phase TiO(2) photoelectrode has been investigated. The mixed-phase TiO(2) particles with varied amounts of rutile, relative to anatase phase, are synthesized by an in situ method where the concentration of sulfate ion is used as a phase-controlling parameter in the formation of TiO(2) using TiCl(4) hydrolysis. The surface area (S(BET)) varies from 33 (pure rutile) to 165 (pure anatase) m(2) g(-1). Generally, both the current density (J(sc)) and photo-conversion efficiency (η) decrease as the rutile content increases. The incorporation of rod-shaped rutile particles causes low uptake of dye due to the reduced surface area, as well as slow electron transport in less efficiently-stacked structure. However, maximum J(sc) (14.63 mA cm(-2)) and η (8.69%) appear when relatively low rutile content (16%) is employed. The reported synergistic effect by the efficient interparticle electron transport from rutile to anatase seems to overbalance the decrease of surface area when small amount of rutile particles is incorporated. 相似文献
992.
Cyriac A Jeon JY Varghese JK Park JH Choi SY Chung YK Lee BY 《Dalton transactions (Cambridge, England : 2003)》2012,41(5):1444-1447
Contrary to the stereotype, Jacobsen's catalyst, chiral (salcy)Co(III)OAc adopts an unusual binding mode. The tetradentate {ONNO} ligand does not form a square plane but wraps cobalt in a cis-β fashion while acetate is chelating. 相似文献
993.
SH Kim da J Kim M Jeong Go Y Soo Ko J Lee Y Kim 《Dalton transactions (Cambridge, England : 2003)》2012,41(38):11619-11626
The synthesis and characterization of LTi(O-i-Pr)(2) (1) and LTiCl(2) (2) complexes containing a new [ONNO]-type tetradentate diamine-diethanolate ligand such as (HOCMe(2)CH(2)NMeCH(2)CH(2)NMeCH(2)CMe(2)OH) (LH(2)) was achieved. Single-crystal X-ray analyses revealed that monomeric complexes 1 and 2 had pseudo-C(2) and pseudo-C(1) symmetric distorted octahedral geometry, respectively. Interestingly, complex 1 has fac-fac geometry for tetradentate L around a Ti centre in both solid and solution, whereas complex 2 has different geometry in solid (mer-fac, C(1)) and solution (fac-fac, C(2)). They are effective catalysts for the controlled ring opening polymerization of l-lactide, as shown by the linearity of the number average of the molecular weight of polylactides versus conversion, as well as narrow PDI values. 相似文献
994.
KS Lim DW Ryu WR Lee EK Koh HC Kim CS Hong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(37):11541-11544
Crystal clear: An end-on (EO) azide-bridged Co(II) layer (see scheme; 1) with coordinated water molecules, long spacer p-XBP4 ligands, and unbound azide anions was evacuated to generate a dehydrated sample of 2. A reversible crystal-to-amorphous structural transformation accompanied by color and magnetic changes takes place between 1 and 2 by using a desolvation-solvation protocol. 相似文献
995.
996.
Koo BH Lim KS Ryu DW Lee WR Koh EK Hong CS 《Chemical communications (Cambridge, England)》2012,48(19):2519-2521
A tetranuclear Er(III) compound chelated with N(2)O(2) donors of a tetradentate Schiff base was produced from the self-assembly of the corresponding chemical species. This intriguing cluster shows field-induced slow relaxation of magnetization. 相似文献
997.
Novel synthesis of amine-stabilized Au–Ag alloy nanoparticles with controlled composition has been devised using poly(ethylenimine)
(PEI) as a reducing and a stabilizing agent simultaneously. The composition of Au–Ag alloy nanoparticles was readily controlled
by varying the initial relative amount of HAuCl4 and AgNO3. Due to the presence of abundant amine functional groups in PEI, which could act as the dissolving ligand for AgCl, the precipitation
problem of Ag+ in the presence of Cl− from the gold salt was avoided. On this basis, the relatively high concentrations of HAuCl4 and AgNO3 salts were used for the fabrication of Au–Ag alloy nanoparticles. The PEI thus plays triple roles in this study that include
the co-reducing agents for HAuCl4 and AgNO3, the stabilizing agents for Au–Ag alloy nanoparticles, and even the dissolving agents for AgCl. As a novel material for use
in catalysis, the Au–Ag alloy nanoparticles including pure Au and Ag samples were exploited as catalysts for the reduction
of 4-nitrophenol in the presence of NaBH4. As the Au content was increased in the Au–Ag alloy nanoparticles, the rate constant of the reduction was exponentially increased
from pure Ag to pure Au. 相似文献
998.
We show that the Kerr metric does not exist as a fully rotating black hole solution to modified Hořava–Lifshitz (HL) gravity
with Λ
W
=0 and λ=1. We do this by showing that the Kerr metric does not satisfy the full equations derived from modified HL gravity. 相似文献
999.
We summarize recent work in which we attempt to make consistent models of LHC physics, from the Pyramid Scheme. The models share much with the NMSSM, in particular, enhanced tree level contributions to the Higgs mass and a preference for small tan??. There are three different singlet fields, and a new strongly coupled gauge theory, so the constraints of perturbative unification are quite different. We outline our general approach to the model, which contains a K?hler potential for three of the low energy fields, which is hard to calculate. Detailed calculations, based on approximations to the K?hler potential, will be presented in a future publication. 相似文献
1000.
Shin Buhm Lee Seo Hyoung Chang Hyang Keun Yoo Moon Jee Yoon Sang Mo Yang Bo Soo Kang 《Current Applied Physics》2012,12(6):1515-1517
We find that resistance switching (RS) phenomena change reversibly between bipolar RS (BRS) and unipolar RS (URS) in a Pt/SrTiOx/Pt cell. For an asymmetric electrode configuration of Ti/SrTiOx/Pt cells whose top and bottom interfaces are Ohmic and Schottky-like rectifying, we determine that BRS only occurs when a positive voltage is applied to the bottom Pt electrode at the forming process. During the set process of BRS in a Pt/SrTiOx/Pt cell, O2 bubbles develop on the top Pt electrode. From the experimental results for a single sample in which both BRS and URS occur, O2? ion movement and consequent interfacial resistance modification might play an important role in BRS but not URS. 相似文献