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81.
We developed a method for the simultaneous quantification of aceclofenac and its three major metabolites in rat plasma. After protein precipitation with acetonitrile including flufenamic acid as an internal standard (IS), aceclofenac, diclofenac, 4'-hydroxyaceclofenac, 4'-hydroxydiclofenac, and the IS were chromatographed on a reverse-phase C18 analytical column. The isocratic mobile phase of acetonitrile/0.1% formic acid (aq; 9:1 [v/v]) was eluted at 0.3 mL/min. Quantification was performed on a triple-quadrupole mass spectrometer using electrospray ionization, and the ion transitions were monitored in selective reaction-monitoring mode. The coefficient of variation in the assay precision was less than 8%, and the accuracy was 92-103%. This method was successfully used to measure the concentrations of aceclofenac and its three major metabolites in rat plasma following the oral administration of a single 20 mg/kg oral dose of aceclofenac. 相似文献
82.
Rahim MA Islam MS Bae TS Choi WS Noh YY Lee HJ 《Langmuir : the ACS journal of surfaces and colloids》2012,28(22):8486-8495
The mixing of Ag ion-doped poly(ethyleneimine) (PEI) and poly(acrylic acid) (PAA) produced Ag ion-doped polyelectrolyte complex particles (PECs) in solution. Positively charged Ag ion-doped PECs (Ag ion PECs) with a spherical shape were deposited alternatively with PAA to form a multilayer assembly. The multilayered film containing Ag ion PECs was reduced to generate a composite nanostructure. Metal nanoparticle (NP)-enriched nanocomposite films were formed by an additional process of the postadsorption of precursors on PECs within the nanocomposite films, which resulted in the enhancement of the catalytic and electrical properties of the composite films. Because the films contain PECs that are responsive to changes in pH and most of the NPs are embedded in the PECs, interesting catalytic properties, which are unexpected in a particle-type catalyst, were observed upon pH changes. As a result of the reversible structural changes of the films and the immobilization of the NPs within the films, the film-type catalysts showed enhanced performance and stability during catalytic reactions under various pH conditions, compared to particle-type catalysts. 相似文献
83.
Min Jeong SeoHeung-Ryoul Noh 《Optics Communications》2012,285(24):5175-5179
We present a theoretical and experimental study of self-rotation of incident elliptically polarized light on a rubidium atomic vapor. We construct density matrix equations, which are then solved numerically, and further averaged over atomic transit times and a Maxwell-Boltzmann velocity distribution. We calculate the rotation angle as a function of detuning for various laser intensities and polarizations. We compare the calculated results with experimental results and find good agreement between them. 相似文献
84.
JB Park K Zong IC Jeon JR Hahn D Stacchiola D Starr K Müller J Noh 《Journal of colloid and interface science》2012,384(1):143-148
The adsorption and thermal stability of 2-octylthieno[3,4-b]thiophene (OTTP) on the Au(111) surfaces have been studied using scanning tunneling microscopy (STM), temperature programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS). UHV-STM studies revealed that the vapor-deposited OTTP on Au(111) generated disordered adlayers with monolayer thickness even at saturation coverage. XPS and TPD studies indicated that OTTP molecules on Au(111) are stable up to 450K and further heating of the sample resulted in thermal decomposition to produce H(2) and H(2)S via C-S bond scission in the thieno-thiophene rings. Dehydrogenation continues to occur above 600K and the molecules were ultimately transformed to carbon clusters at 900K. Highly resolved air-STM images showed that OTTP adlayers on Au(111) prepared from solution are composed of a well-ordered and low-coverage phase where the molecules lie flat on the surface, which can be assigned as a (9×2√33)R5° structure. Finally, based on analysis of STM, TPD, and XPS results, we propose a thermal decomposition mechanism of OTTP on Au(111) as a function of annealing temperature. 相似文献
85.
Salicylimine-based fluorescent chemosensor for aluminum ions and application to bioimaging 总被引:1,自引:0,他引:1
Kim S Noh JY Kim KY Kim JH Kang HK Nam SW Kim SH Park S Kim C Kim J 《Inorganic chemistry》2012,51(6):3597-3602
In this study, an assay to quantify the presence of aluminum ions using a salicylimine-based receptor was developed utilizing turn-on fluorescence enhancement. Upon treatment with aluminum ions, the fluorescence of the sensor was enhanced at 510 nm due to formation of a 1:1 complex between the chemosensor and the aluminum ions at room temperature. As the concentration of Al(3+) was increased, the fluorescence gradually increased. Other metal ions, such as Na(+), Ag(+), K(+), Ca(2+), Mg(2+), Hg(2+), Mn(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Pb(2+), Cr(3+), Fe(3+), and In(3+), had no such significant effect on the fluorescence. In addition, we show that the probe could be used to map intracellular Al(3+) distribution in live cells by confocal microscopy. 相似文献
86.
Keun-byoung Yoon Yeon Seok Choi Seok Kyun Noh Dong-ho Lee 《Macromolecular Symposia》2007,260(1):27-33
The copolymerization of ethylene and norbornene (N) was carried out with iPr(Cp)(Flu)ZrCl2 catalyst and modified methylaluminoxane (MMAO) cocatalyst. The catalytic activity was dependent on the structure of MMAO, i.e., MMAO-4 exhibited higher catalyst activity than MMAO-3A containing more i-butyl groups. The glass transition temperature (Tg) and the composition of the produced copolymer were not affected by MMAO type. With styrene derivatives as 3rd monomer, Tg of copolymer increased while the catalytic activity decreased. With the addition of 3rd monomer, not only the content of 3rd monomer but also the content of N increased. 相似文献
87.
We present low temperature photoluminescence investigations of the exciton ground state of In0.14Ga0.86As/GaAs quantum wells (QW) in the presence of pulsed magnetic fields up to 50 T. The exciton in-plane reduced mass and the heavy-hole in-plane mass are determined from the best fit of theoretical calculations to the magnetic field dependence of PL peaks. When the QW thickness decreases, their masses increases due to valence-band mixing effect. 相似文献
88.
89.
Photocycloaddition of furan to 1-naphthalenecarbonitrile (1) was reinvestigated. Irradiation of the mixture through Pyrex filter yielded endo-[4+4] adduct (2) and syn-[2+2] adduct (4). Considering the secondary orbital interaction in the singlet-state [4+4] photocycloaddition, the favorable formation of exo-[4+4] cyclodimer (3) over 2 followed by a facile Cope rearrangement was proposed for the formation of 4, and confirmed by a low temperature irradiation experiment. 相似文献
90.
Chong Shik Chin Hyungeui Lee Myung Ki Lee Soyoung Noh Min-Sik Eum Seunggweon Hong 《Journal of organometallic chemistry》2005,690(5):1306-1313
Alkyl-carbonyl-iridium [Ir(CH3)(CO)(η2-O2CR′)(PPh3)2]+ (1, R′ = CH3, Ph, p-C6H4CH3) react with alkynes (RCCH; R = Ph, p-C6H4CH3) in the presence of NEt3 to give acyl-alkynyl-iridium Ir(C(O)CH3)(-CCR)(η2-O2CR′)(PPh3)2 (4) which further react with RCCH to give alkyl-carbonyl-cis-bis(alkynyl) iridium Ir(CH3)(CO)(CCR)2(PPh3)2 (5). cis-Bis(alkenyl)iridium complexes, Ir(-CHCH2)2(η2-O2CCH3)(PPh3)2 (6) and (η2-O2CCH3)(PPh3)2 (7) react with substituted alkynes RCCH (R = Ph, p-C6H4CH3, cyclohex-1-enyl) to give cis-bis(alkynyl) Ir(CCR)2(η2-O2CCH3)(PPh3)2 (9) that further react with RCCH to undergo the alkyne insertion reaction into the Ir-O bond to produce iridacycles containing vinyl acetate ligands, (-CCR)2(PPh3)2 (8). 相似文献