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121.
Kirby AJ Souza BS Medeiros M Priebe JP Manfredi AM Nome F 《Chemical communications (Cambridge, England)》2008,(37):4428-4429
The reaction of hydroxylamine with 2,4-dinitrophenyl diethyl phosphate gives the O-phosphorylated product, which is rapidly converted to hydrazine and nitrogen gas in the presence of the excess of hydroxylamine. 相似文献
122.
Farrukh MA Beber RC Priebe JP Lal Satnami M Micke GA Costa AC Fiedler HD Bunton CA Nome F 《Langmuir : the ACS journal of surfaces and colloids》2008,24(22):12995-13000
The reaction of I (-) with methyl naphthalene-2-sulfonate (MeONs) is accelerated by the micellized sulfobetaine surfactants N-decyl, N-dodecyl, N-tetradecyl, and N-hexadecyl- N, N-dimethylammonio-1-propanesulfonate. Concentrations of micellar-bound I (-) were determined by using ion-selective electrodes (ISE), and capillary electrophoresis. At low concentrations, I (-) incorporation fits Langmuir isotherms and is related to changes in micellar surface potentials. Rate effects of dilute KI are fitted quantitatively by a pseudophase model that describes I (-) binding in terms of a sorption isotherm, but at higher [KI], where the simple model predicts saturation, rates increase due to electrolyte invasion. This model considers transfer equilibria of both reactants between water and micelles and second-order rate constants in each pseudophase. Estimated second-order rate constants for reaction of MeONs with I (-) in the micellar pseudophase are 3.2- to 3.5-fold higher than the second-order rate constant, k 2w, in water, depending on surfactant structure and assumptions in the treatment. 相似文献
123.
A differential pulse voltammetric method for the determination of nitrate has been described, which is applicable to the
analysis of natural water samples with nitrate levels greater than 2.8 × 10−6 M. A reduction peak for the nitrate ions at a freshly copper plated glassy carbon electrode was observed at about −0.50 V
vs Ag ∣AgCl∣KClsatd electrode in a solution of 2.0 × 10−2 M Cu2+, 0.5 M H2SO4 and 1.0 × 10−3 M KCl and exploited for analytical purposes. The working linear range was established by regression analysis and found to
extend from 2.8 ×10−6 M to 8.0 × 10−5 M. The proposed method was applied for the determination of nitrate in natural waters. The detection limit of the method
was 2.8 × 10−6 M and the sensitivity was 0.9683 A·L/mol. The possible interferences by some ions such as phosphate, nitrite and some halides
were determined and found to lead to shifts of the peak position and increasing the peak heights.
Received March 15, 1999. Revision July 9, 1999. 相似文献
124.
Ezgi BAYRAKDAR ATE Tuba GÜRKAYNAK ALTINEK Mehmet Ali Faruk
KSÜZ
MER 《Turkish Journal of Chemistry》2021,45(4):967
Nickel catalysts supported on γ-Al2O3 were synthesized in the presence of polyvinylpyrrolidone (PVP) using both alkaline polyol method and hydrazine reduction method while fixing the weight ratio of [(PVP)]/[Ni(CH3COO)2·4H2O] at 2. The effects of hydrazine [N2H5OH]/[Ni] and [NaOH]/[Ni] molar ratios on the structural properties of the catalysts were characterized by transmission electron microscopy (HRTEM) and by X-ray diffraction (XRD). The average of monodispersed Ni nanoparticles ranged between 8.0 and 13.0 nm. The catalytic tests were performed for the partial oxidation of methane in the temperature range of 600–800 °C under a flow rate of 157,500 L kg–1 hr–1 with CH4/O2= 2. At the molar ratio of [NaOH]/[Ni] = 2, the resultant nickel nanoparticles on alumina was established completely without impurities; thus, it demonstrated the highest catalytic activity, 88% for CH4 conversion, and H2 selectivity, 90.60%. The optimum [N2H5OH]/[Ni] ratio was determined as 4.1, which means a good catalytic performance and 89.35% selectivity to H2 for the partial oxidation of methane. 相似文献
125.
From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of virial coefficients, one can produce the known results in d=3 and d=2. But more importantly we found that, the virial coefficients of Bose and Fermi gases become identical (except the second virial coefficient, where the sign is different) when the gases are trapped under harmonic potential in d=1. This result suggests the equivalence between Bose and Fermi gases established in d=1 (J. Stat. Phys. DOI 10.1007/s10955-015-1344-4). Also, it is found that the virial coefficients of two-dimensional free Bose (Fermi) gas are equal to the virial coefficients of one-dimensional harmonically trapped Bose (Fermi) gas. 相似文献
126.
Periodica Mathematica Hungarica - In this paper, we first prove the existence and uniqueness of the solutions for a delayed hyperbolic partial differential equation by applying the progressive... 相似文献
127.
Donny W.H. Merkx Faruk Delić Peter A. Wierenga Marie Hennebelle John P.M. van Duynhoven 《Magnetic resonance in chemistry : MRC》2019,57(9):540-547
Lipid oxidation is the main reason for the limited shelf life of mayonnaise. One of the main catalysts of this process is iron, which is introduced in its ferric (Fe(III)) form via phosvitin, an egg yolk phosphoprotein rich in phosphoserines. The binding of Fe(III) to phosvitin and its ability to establish a redox couple with Fe(II) is believed to determine the oxidation rate of unsaturated lipids. In this work, a 31P NMR based method was developed to quantify loading of phosvitin with Fe(III) and its reductive release. Both features could be quantified in model phosvitin solutions by exploiting the paramagnetic broadening of 31P NMR signal of phosphoserine residues by Fe(III). This method was then successfully applied to quantify the phosvitin-Fe(III) loading in mayonnaise water phase by liquid NMR, whereas 31P NMR MAS could only provide a qualitative measure. The 31P NMR method showed a direct relation between loading of the Fe(III)-phosvitin complex and lipid oxidation. 相似文献
128.
mer Faruk Karata Erdin Sezgin
mer Aydn Mustafa ulha 《Colloids and surfaces. B, Biointerfaces》2009,71(2):315-318
Mitochondrion is one of the most important organelles in cells with several vital responsibilities. The consequence of a deficiency in the function of mitochondrion could result with the wide range of diseases and disorders. In this study, we investigated the feasibility of utilizing surface-enhanced Raman scattering (SERS) to understand the mode of interaction of gold nanoparticles (GNPs) with mitochondria. The living lung cancer cells and the isolated mitochondria from these cells were treated with gold colloidal suspension for SERS experiments. The AFM images of the mitochondria confirmed that the treatment did not cause substantial damage to mitochondria. The localization of GNPs in living cells is investigated with confocal microscopy and found that GNPs form aggregates in the cytosol away from the mitochondria. However, SERS spectra obtained from isolated mitochondria and living cells indicate that GNPs escaped from the endosomes or entered into the living cell through another route may be in contact with mitochondria in a living cell. The findings of this study indicate that SERS can be used for mitochondrial research. 相似文献
129.
We study the family of weighted harmonic Bloch spaces \(b_\alpha , \alpha \in {\mathbb {R}}\), on the unit ball of \({\mathbb {R}}^n\). We provide characterizations in terms of partial and radial derivatives and certain radial differential operators that are more compatible with reproducing kernels of harmonic Bergman–Besov spaces. We consider a class of integral operators related to harmonic Bergman projection and determine precisely when they are bounded on \(L^\infty _\alpha \). We define projections from \(L^\infty _\alpha \) to \(b_\alpha \) and as a consequence obtain integral representations. We solve the Gleason problem and provide atomic decomposition for all \(b_\alpha , \alpha \in {\mathbb {R}}\). Finally we give an oscillatory characterization of \(b_\alpha \) when \(\alpha >-1\). 相似文献
130.