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81.
Recyclable antimicrobial magnetic nanoparticles, Fe3O4@P(St-co-AcQAC), were prepared through surfactantfree seeded emulsion polymerization involving a polymerizable, hydrophobic quaternary ammonium compound (QAC). These antimicrobial magnetic nanoparticles demonstrated excellent antimicrobial activities against both Grampositive and Gram-negative bacteria, and can be reused for multiple times. 相似文献
82.
A new type of optode membrane for the determination of alcohols, such as methanol, ethanol, propan-1-ol and propan-2-ol etc, is presented that can be exploited in optical and fibre-optic sensors. It is based on the use of a new lipophilic fluorescent reagent, namely fluorescein octadecyl ester (FODE), which is immobilized in a plasticized PVC membrane. The response mechanism relies on the fact that FODE can reversibly recognize alcohol molecules due to the hydrogen bonding formation between FODE and alcohol molecules. The analytical information in this membrane is the enhancement of the relative fluorescence intensity measured at 527 nm (463 nm, excitation). Under the optimum condition, the membrane has a wide measuring range for alcohol samples. The membrane has been applied to determine the concentration of ethanol in alcoholic drinks with satisfactory results. 相似文献
83.
84.
B. Hu Y. Song L. Wang Q. Zhang J. Li K. Wei Y. Chen L. Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(1):231-233
Summary Electronic stopping power of 19F in Ni, Pd and Gd was measured and compared to Mstar and SRIM calculation as well as experimental results published in literature.
It turns out that the present electronic stopping power agrees reasonably well with them. 相似文献
85.
Chowdhury Wasimul Q. Idehara Kenji Maeda Isamu Umeda Fusako Yagi Kiyohito Miura Yoshiharu Mizoguchi Tadashi 《Applied biochemistry and biotechnology》1996,57(1):361-366
Applied Biochemistry and Biotechnology - A marine photosynthetic bacterium,Rhodopseudomonas sp. strain W-1S, accumulated polyhydroxybutyrate (PHB) to 56% of the dry cell weight under microaerobic... 相似文献
86.
H. Sh. Bai H. X. Jin H. Q. Fan J. Du F. Wang D. M. Chen Zh. Cheng 《Journal of Radioanalytical and Nuclear Chemistry》1998,236(1-2):87-95
The behavior of153Sm-EDTMP in vitro and vivo is analyzed by the size exclusion HPLC. The experimental results show that EDTMP amounts have an
obvious effect on the stability in vitro and uptake of153Sm-EDTMP in the liver. HPLC analysis of urine sample indicates that153Sm-EDTMP es excreted in the original form. The behavior in vivo of153Sm-EDTMP containing 4 μg is similar to that of153Sm-EDTMP containing 50 μg EDTMP at 1 h post-injection. 相似文献
87.
We extend our method of systematic removal of secular terms in a singular perturbation treatment of the Boltzmann equation with small Knudsen numbers to the initial layer. The requirement that the solution through the initial layer should connect smoothly to the normal solution removes an ambiguity noted in our previous paper. We show that removal of secular terms improves Grad's solution for the initial layer and reintroduces soundlike modes associated with higher moments, first found by Wang Chang and Uhlenbeck. 相似文献
88.
Ch. V. Subba Reddy Y. Y. Qi W. Jin Q. Y. Zhu Z. R. Deng W. Chen Sun-il Mho 《Journal of Solid State Electrochemistry》2007,11(9):1239-1243
Molybdenum trioxide (MoO3) xerogel films modified with poly(vinyl alcohol)+poly(vinyl pyrrolidone) (PVP+PVA) polyblends were obtained by ion-exchange
method with sol-gel technique. Investigations were conducted using X-ray “diffractometry”, Fourier transform infrared spectroscopy,
and cyclic voltammetry. The results show that the H atoms in polyblend are H-bonded with the O atoms in the Mo=O bonds of
MoO3 xerogel, which effectively shield the electrostatic interaction between MoO3 interlayer and Li+ ions when MoO3 xerogel is modified by the intercalation of (PVP+PVA). The reversibility of the insertion/extraction of Li+ ions is greatly improved by the modification with polyblend of MoO3 nanocomposite films. MoO3 and (PVP+PVA)
x
MoO3 (x = 0, 0.5) nanobelts were obtained by a simple hydrothermal process from MoO3 sol. The electrochemical cells with configuration Li/(LiPF6+EC+DMC)/MoO3 modified by (PVP+PVA) were fabricated and their discharge profiles studied. 相似文献
89.
Lin CS Zhang RQ Lee ST Elstner M Frauenheim T Wan LJ 《The journal of physical chemistry. B》2005,109(29):14183-14188
The assembly of small water clusters (H2O)n, n = 1-6, on a graphite surface is studied using a density functional tight-binding method complemented with an empirical van der Waals force correction, with confirmation using second-order M?ller-Plesset perturbation theory. It is shown that the optimized geometry of the water hexamer may change its original structure to an isoenergy one when interacting with a graphite surface in some specific orientation, while the smaller water cluster will maintain its cyclic or linear configurations (for the water dimer). The binding energy of water clusters interacting with graphite is dependent on the number of water molecules that form hydrogen bonds, but is independent of the water cluster size. These physically adsorbed water clusters show little change in their IR peak position and leave an almost perfect graphite surface. 相似文献
90.
In order to improve the photosensitizing activity of HB further, the complex of 5,8-di-Br-HB with Al(3+) was first designed and synthesized in high yield. 5,8-di-Br-HB forms a 2:1 type (metal-ligand ratio) complex with Al(3+) measured by molar ratio and continuous variation methods. The new photosensitizer was characterized by UV-Vis, IR, 1H NMR and elemental analysis measurements. Based on the above experimental results, we first proposed a polymer-like structural model of the complex. The water-solubility and red absorption of the [Al(2)(5,8-di-Br-HB)Cl(4)](n) complex are both enhanced over hypocrellin B. In addition, the EPR and spectrophotometric measurements demonstrate that semiquinone anion radical of [Al(2)(5,8-di-Br-HB)Cl(4)](n) can be produced by [Al(2)(5,8-di-Br-HB)Cl(4)](n) photosensitization. The generation efficiency of ([Al(2)(5,8-di-Br-HB)Cl(4)](n))(.-) is almost equal to that of HB(.-). These results obtained indicated that [Al(2)(5,8-di-Br-HB)Cl(4)](n)was at least a favorable Type I phototherapeutic agent. 相似文献