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61.
Alla Zablotskaya Izolda Segal Mikhail Maiorov Elmars Blums Ilona Domracheva 《Journal of magnetism and magnetic materials》2009,321(10):1428-1432
We present the results of the interaction of iron oxide nanoparticles with some biologically active surfactants, namely, oleic acid and cytotoxic alkanolamine derivatives. Physico-chemical properties, as magnetization, magnetite concentration and particle diameter, of the prepared magnetic samples were studied. The nanoparticle size of 11 nm for toluene magnetic fluid determined by TEM is in good agreement with the data obtained by the method of magnetogranulometry. In vitro cytotoxic effect of water-soluble nanoparticles with different iron oxide:oleic acid molar ratio were revealed against human fibrosarcoma and mouse hepatoma cells. In vivo results using a sarcoma mouse model showed observable antitumor action. 相似文献
62.
Jolanta Rousseau Vilija Kriščiūnienė Ilona Rimkevičiūtė Cyril Rousseau Virginė Amankavičienė Algirdas Šačkus Arnaud Tatibouët Patrick Rollin 《Monatshefte für Chemie / Chemical Monthly》2009,140(3):339-348
Abstract Modular conditions for the formation of thioureas or pyrimidine-4-one-2-thiones connected to the benzo[b]thiophene, benzene and indole structures were performed. A benzo[b]thiophene isothiocyanate derivative was used as a model to study the condensation with simple aromatic amines and amino-l-sorbose derivative. The construction of pyrimidine-4-one-2-thiones using basic conditions afforded efficiently new heterocyclic
aromatics, which were further transformed using the alkylated sulfur as a leaving group in palladium-catalyzed cross-coupling
reactions.
Graphical abstract
相似文献
63.
Benedek Károlyi Zsolt Gengeliczki Gábor Vass László Szepes 《Journal of organometallic chemistry》2009,694(18):2923-2926
A new series of isonitrile-substituted cobalt tricarbonyl nitrosyl (Co(CO)2(NO)CNR, R = Me, Et, nPr, iPr, nBu, nPe, CH2Si(CH3)3) has been synthesized, and their He I ultraviolet photoelectron spectra are reported. The assignment of the bands in the low energy part of the spectra was performed with the aid of DFT calculations. The first vertical ionization energies of the complexes were found to be 7.73 (CNMe), 7.58 (CNEt), 7.59 (CNnPr), 7.70 (CNnBu), 7.67 (CNnPe), 7.77 (CNiPr), and 7.54 ± 0.03 eV (CNCH2Si(CH3)3). In the case of nPr- and CH2Si(CH3)3- substitutions, He II photoelectron spectra were also recorded. The relative importance of electronic and steric effects of the isonitrile ligands, as a function of the size of group –R, is discussed. 相似文献
64.
Dominique Brunet József Vass Edward R. Vrscay Zhou Wang 《Applied Mathematics Letters》2012,25(11):1921-1925
We construct metrics from the geodesics of the Structural Similarity index, an image quality assessment measure. An analytical solution is given for the simple case of zero stability constants, and the general solution involving the numerical solution of a nonlinear equation is also found. 相似文献
65.
In this tutorial review we summarize the standard approaches to describe aerosol formation from atmospheric vapours and subsequent growth - with a particular emphasis on the interplay between equilibrium thermodynamics and non-equilibrium transport. We review the use of thermodynamics in describing phase equilibria and formation of aerosol particles from supersaturated vapour via nucleation. We also discuss the kinetics of cluster formation and transport phenomena, which are used to describe dynamic mass transport between the gaseous and condensed phases in a non-equilibrium system. Finally, we put these theories into the context of atmospheric observations of aerosol formation and growth. 相似文献
66.
Pasinszki T Vass G Klapstein D Westwood NP 《The journal of physical chemistry. A》2012,116(13):3396-3403
Cyanoformyl chloride and cyanoformyl bromide, XC(O)CN (X = Cl and Br), have been investigated in the gas phase by UV photoelectron and mid-infrared spectroscopies. The ground-state geometries of the neutral molecules have been obtained from quantum-chemical calculations at the B3LYP and CCSD(T) levels using the aug-cc-pVTZ basis set. The individual spectroscopies provide a detailed investigation into the vibrational and electronic character of the molecules and are supported by quantum-chemical calculations. The results are compared to data for structurally and chemically related molecules. 相似文献
67.
E. Vass 《Solid State Communications》1985,55(9):847-849
The average energy loss P of hot electrons due to the interaction with acoustic bulk phonons is calculated and used to determine the electron heating temperature Δ as a function of the input power eμE2. It is found that P creases proportional to Δ2 and is independent of the carrier concentration. Consequently the ratio Δ/√ eμE2 turns out to be a constant for for n-GaAs) in agreement with the experimental data deduced from FIR-emission experiments at T = 4.2 K. 相似文献
68.
We show that on finite incidence algebras every local derivation is a derivation. 相似文献
69.
Structure and Magnetic Properties of PrLiGe, TbLiGe, DyLiGe, YbLiGe, and YbLiBi The compounds PrLiGe, TbLiGe, DyLiGe, YbLiGe, and YbLiBi were prepared and investigated by X-ray methods and magnetic measurements. Powder patterns show that PrLiGe, TbLiGe, DyLiGe, and YbLiGe crystallize isotypically. Single crystal investigations of PrLiGe and YbLiGe gave as a result a modified Fe2P-type structure. YbLiBi seems to crystallize isotypically to the structure of YLiSn which can be described as a “filled” Wurtzit lattice [1, 2]. Measurements of the magnetic susceptibilities point to electrovalent composition with Pr3+ and Yb3+ in PrLiGe and YbLiGe and Yb2+ in YbLiBi, respectively. 相似文献
70.
Summary A flow-through triangle programmed coulometric titration technique is worked out for the determination of phenothiazine compounds. The oxidation reaction of phenothiazines with hypobromite ion served as titration reaction. A biamperometric detector cell has been used for following the titration process. The titration technique has been used for the determination of the drug content (average and individual) of chlorpromazine, promethazine, diethazine and trifluoperazine in pharmaceutical preparations. The relative standard deviation was in the range of 2.0 to 3.5%.
Bestimmung des Wirkstoffgehaltes von Phenothiazin-haltigen Pharmazeutica mit Hilfe einer Dreieck-programmierten Durchflu\-Titration相似文献