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41.
Brasch M de la Escosura A Ma Y Uetrecht C Heck AJ Torres T Cornelissen JJ 《Journal of the American Chemical Society》2011,133(18):6878-6881
We report herein the encapsulation of a water-soluble phthalocyanine (Pc) into virus-like particles (VLPs) of two different sizes, depending on the conditions. At neutral pH, the cooperative encapsulation/templated assembly of the particles induces the formation of Pc stacks instead of Pc dimers, due to an increased confinement concentration. The Pc-containing VLPs may potentially be used as photosensitizer/vehicle systems for biomedical applications such as photodynamic therapy. 相似文献
42.
Raut S Heck A Vishwanatha J Sarkar P Mody A Luchowski R Gryczynski Z Gryczynski I 《Journal of photochemistry and photobiology. B, Biology》2011,102(3):241-245
The antioxidant properties of aminobenzamide cysteine (ABZ Cys) makes it a molecule that can potentially be used as a drug in oxidative stress related diseases and delivered in the form of a nanoparticles. Here we have studied the photo-physical properties of ABZ Cys, a fluorescent analogue of a popular antioxidant N-acetyl cysteine (NAC). We have compared ABZ Cys steady state and time-resolved fluorescence properties with its parent compounds anthranilic acid and anthranilamide in solution as well as in poly-vinyl alcohol (PVA) polymer films. ABZ Cys did not show any significant shift in absorption after entrapment in PVA film, but there was a shift towards shorter wavelengths in the emission peak compared to the phosphate buffer solution. Fluorescence lifetimes and quantum yields indicated a slight quenching of ABZ Cys fluorescence in comparison to the cysteine-less parent compounds. We also demonstrated that very low concentrations of ABZ Cys, such as 100 nM, are readily detected by a commercial spectrofluorometer. Hence we have established the possible use of ABZ Cys in biomedical applications. 相似文献
43.
Mark S. Baird Alexander V. Stepakov Jurgen Kopf Rafael R. Kostikov 《Tetrahedron》2007,63(32):7717-7726
The synthesis of 2,2-dibromocyclopropane-1,1-dicarboxylic acids is described. Reaction of substituted 1,1-dibromo-2-acyloxymethylcyclopropanes with methyl lithium at low temperature leads to a bromine-lithium exchange and then either formal protonation to give the corresponding monobromocyclopropanes or intramolecular cyclisation to give a substituted 3-oxabicyclo[3.1.0]hexane. Oxidative ring opening of these compounds leads stereoselectively to 1,1,2,2-tetrasubstituted cyclopropanes with four functionalities on the ring. 相似文献
44.
A computer program is given for the identification of edible oils from their fatty acid ratios. The program was used with the Hewlett-Packard 3354 Laboratory Automation System in autocall mode to identify a number of vegetable oils from the fatty acid ratios determined by gas chromatography of the trans-esterified oil samples. 相似文献
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46.
A. Arefiev A. Babaev A. Bamberger H.-J. Brundiers G. Eliseev U. Fischer D. Friedrich Yu. Galaktionov Yu. Gorodkov R. hartung W. Heck Yu. Kamyshkov V. Lubimov R. Maier V. Plyaskin V. Pojidaev K. Runge O. Schaile Ch. Weber 《Nuclear Physics B》1984,232(3):365-397
The np elastic differential cross section has been measured for incident neutron momenta 100–400 GeV/c in the |t| range 6 · 10?6 ? 5 · 10?1 (GeV/c)2. The np data of this experiment provide a first direct measurement of the hadronic amplitude for |t| < 10?2 (GeV/c)2, which is consistent with the extrapolations from higher |t| values. Our data for |t| < 10?4 (GeV/c)2 are consistent with a rise which can be attributed to Schwinger scattering, caused by the interaction of the neutron magnetic moment with the proton. 相似文献
47.
By γ-γ coincidence measurements following the 57Fe(12C, 2nγ) reaction at E12C = 40 MeV several new states above 1.5 MeV excitation energy in 67Ge have been established. Spin and parity assignments on the basis of the angular distribution, linear polarization and γ-ray yield function indicate very similar structures in 67, 69Ge. The positive-parity states can be followed up to the state at Ex = 3.07 MeV followed by a sequence of negative-parity high-spin states at nearly the same excitation energy relative to the single-particle state as in the neighbouring nucleus 69Ge where these states were found to have strong single-particle admixtures. A reinvestigation of the spin of the Ex = 2.75 MeV level in 69Ge resulting in a change of its spin from and for all spins above, removed the discrepancy concerning the spin assignments of corresponding levels in 67, 69Ge. The excitation pattern of the Ge isotopes with 34 ≦ N ≦ 39 clearly indicate same structures probably due to the strong competition between collective and single-particle excitations along the whole chain similar to the results for the Zn isotopes. 相似文献
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49.
It is shown that the solutions of a (spatially) discrete model of the Boltzmann equation converge in a weak sense as the lattice spacing approaches zero. The method follows a compactness argument of Arkeryd. 相似文献
50.