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981.
982.
983.
984.
Fan Xia Dr. Xu Hou Liuxuan Cao Lin Wang Jianming Xue Prof. Guangzhao Zhang Prof. Yanlin Song Prof. Daoben Zhu Prof. Yugang Wang Prof. Lei Jiang Prof. 《Chemphyschem》2010,11(4):859-864
Herein we demonstrate a fully abiotic smart single‐nanopore device that rectifies ionic current in response to the temperature. The temperature‐responsive nanopore ionic rectifier can be switched between a rectifying state below 34 °C and a non‐rectifying state above 38 °C actuated by the phase transition of the poly(N‐isopropylacrylamide) [PNIPAM] brushes. On the rectifying state, the rectifying efficiency can be enhanced by the dehydration of the attached PNIPAM brushes below the LCST. When the PNIPAM brushes have sufficiently collapsed, the nanopore switches to the non‐rectifying state. The concept of the temperature‐responsive current rectification in chemically‐modified nanopores paves a new way for controlling the preferential direction of the ion transport in nanofluidics by modulating the temperature, which has the potential to build novel nanomachines with smart fluidic communication functions for future lab‐on‐chip devices. 相似文献
985.
Serial analysis of gene expression (SAGE) is a powerful tool to obtain gene expression profiles. Clustering analysis is a valuable technique for analyzing SAGE data. In this paper, we propose an adaptive clustering method for SAGE data analysis, namely, PoissonAPS. The method incorporates a novel clustering algorithm, Affinity Propagation (AP). While AP algorithm has demonstrated good performance on many different data sets, it also faces several limitations. PoissonAPS overcomes the limitations of AP using the clustering validation measure as a cost function of merging and splitting, and as a result, it can automatically cluster SAGE data without user-specified parameters. We evaluated PoissonAPS and compared its performance with other methods on several real life SAGE datasets. The experimental results show that PoissonAPS can produce meaningful and interpretable clusters for SAGE data. 相似文献
986.
Chun Lin Wenjun Luo Sheng Zhang Zhenbin Zhang Weiguang Zhang Shengrun Zheng Jun Fan Weishan Li Qing Qin Ziyuan Guo 《Journal of separation science》2010,33(11):1558-1562
Two types of chiral stationary phases for HPLC based on π‐acidic or π‐basic perphenylcarbamoylated β‐CDs were synthesized. The relative structural features of the two effective chiral selectors are discussed and compared in both normal‐phase and RP modes. In addition, the nature and concentration of alcoholic modifiers were varied for optimal separation in normal phase and the structural variation of the analytes was also examined. The results showed that hydrogen bonding, steric effect and π‐acidic–π‐basic interaction contributed greatly to enantioseparation. Upon comparison, some of the differences in the separation behavior of the two types of chiral stationary phases might be due to the π‐acidic or π‐basic phenylcarbamate groups. 相似文献
987.
R. Xu D. Li J. Wang Y. X. Kong B. X. Wang Y. M. Kong T. T. Fan B. Liu 《Russian Journal of Coordination Chemistry》2010,36(11):810-819
Two novel ethylenediaminium salt of europium complexes with aminopolycarboxylic acid ligands, (EnH2)3[EuIII(Ttha)]2 · 11H2O (I) (En is ethylenediamine, H6Ttha is triethylenetetramine-N,N,N′,N″,N‴,N‴-hexaacetic acid) and (EnH2)[EuIII(Egta)(H2O)]2 · 6H2O (II) (H4Egta is ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) complexes were synthesized, and their crystal structures
were determined by single-crystal X-ray diffraction techniques. Both of the two complexes adopt nine-coordinate structures
with the pseudo-monocapped square antiprism and crystallize in the monoclinic crystal system with the P21/n space group. The crystal data for complex I are as follows: a = 17.8262(8), b = 19.3137(5), c = 20.6233(8) ?, β = 111.301(2)°, V = 6615.3(4) ?3, Z = 8, ρ
c
= 1.677 mg/m3, μ = 1.981 mm−1, F(000) = 3432, R = 0.0308, and wR = 0.0737 for 43622 observed reflections with I ≥ 2σ(I). The crystal data for complex II are as follows: a = 12.952(3), b = 12.618(2), c = 14.809(3) ?, β = 105.695(2)°, V = 2330.0(8) ?3, Z = 4, ρ
c
= 1.800 mg/m3, μ = 2.765 mm−1, F(000) = 1276, R = 0.0297, and wR = 0.0638 for 18416 observed reflections with I ≥ 2σ(I). One remarkable feature of the two complexes is that the protonated [EnH22+] cations conjugating to [EuIII(Ttha)]26− and [EuIII(Egta)(H2O)]22− complex anions are reviewed, respectively, which open the path for the EuIII complexes conjugating with other various biomolecules. 相似文献
988.
Y. H. Fan Y. F. Wang C. F. Bi Q. Wang X. Zhang X. Y. Liu 《Russian Journal of Coordination Chemistry》2010,36(7):509-513
A new Schiff base ligand C19H13NO5(H2L) was synthesized using 2-aminoterephthalic acid and 2-hydroxy-1-naphthaldehyde. A complex of this ligand [Cu(C19H11NO5)(C2H6O)] n was synthesized and characterized by IR, UV, fluorescence spectroscopy and X-ray diffraction single-crystal analysis. The crystal crystallizes in the monoclinic system, space group Pbca with a = 8.7745(18), b = 18.613(4), c = 24.644(5) Å, V = 4024.9(14) Å3, Z = 8, F(000) = 1816, S = 1.009, ρ calcd = 1.462 g cm?3, μ = 1.122 mm?1, the final R = 0.0477 and wR = 0.1594 for 4609 observed reflections (I > 2σ(I)). The Cu(II) is five-coordinated by one N atom and two O atoms from the Schiff base ligand and two carboxylate O atoms from another two ligands to form a distorted square-pyramidal geometry. Each ligand serves as a bridging ligand to link Cu2+ ions, leading to a two-dimensional coordination polymer. The fluorescence properties of the ligand and complex were also studied. The ligand shows strong fluorescence, and the fluorescence intensity is weakened after the Cu(II) complex formed. 相似文献
989.
L. Q. Zhang T. T. Fan J. Wang B. Liu D. Li G. X. Han R. Xu X. D. Zhang 《Russian Journal of Coordination Chemistry》2010,36(5):389-395
The title complexes (NH4)3[YIII(Nta)2] (I) (H3Nta = nitrilotriacetic acid) and {K[YIII(Egta)] · 4H2O}
n
(II) (H4Egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) were prepared, and their molecular and crystal structures
were determined by single-crystal X-ray diffraction techniques. Complex I crystallizes in the rhombohedral crystal system with R
$
\bar 3
$
\bar 3
c space group. The central Y3+ ion is eight-coordinated by two nitrogen and six oxygen atoms, which come from two tetradentate Nta ligands. The crystal
data are as follows: a = 7.9340(14) ?, c = 54.611(15) ?, V = 2977.1(11) ?3, Z = 6, ρcalcd = 1.738 mg/cm3, μ = 3.011 mm−1, F(000) = 1596, R = 0.0234 and wR = 0.0641 for 686 observed reflections with I ≥ 2σ(I). The {K[YIII(Egta)] · 4H2O}
n
is nine-coordinated by two nitrogen and seven oxygen atoms and produces a 1D unlimited zigzag-type chain through a bridging
carboxylic group. {K[YIII(Egta)] · 4H2O}
n
crystallizes in the monoclinic crystal system with C2/c space group. The crystal data are as follows: a = 37.588(5) ?, b = 13.7101(19) ?, c = 8.6070(12) ?, β = 99.929(2)°, V = 4369.0(11) ?3, Z = 8, ρcalcd = 1.753 mg/cm3, μ = 2.934 mm−1, F(000) = 2368, R = 0.0385 and wR = 0.0800 for 4082 observed reflections with I ≥ 2σ(I). 相似文献
990.
Guangpeng Zhou Yulin Yang Ruiqing Fan Xinrong Liu Hengwu Hong Fuping Wang 《Solid State Sciences》2010,12(7):1103-1106
Using H3PO3 as a phosphorus source and oxalic acid as a reducing agent, the first three-dimensional open-framework gallium phosphate–phosphite formula as (C6N2H18)2(C6N2H17)Ga15(OH)8(PO4)2(HPO4)12(HPO3)6·2H2O (1), has been hydrothermally synthesized in the presence of N,N,N′,N′-tetramethylenediamine (TMEDA) as a structure-directing agent. Compound 1 crystallizes in trigonal system with space group P ? 3, a = b = 19.046(3) Å, c = 8.3306(17) Å, γ = 120°, V = 2617.1(7) Å3, and Z = 1. Its 3-D network is based on alternated Ga-centered (GaO4 tetrahedra, GaO5 trigonal bipyramids, and GaO6 octahedra) and P-centered (PO43?, HPO42?, and HPO32?) units. Protonated organic amines and water molecules are located in the 12-membered ring channels. 相似文献