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41.
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.
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.
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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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 172+ 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 92+ 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 152+to172+ 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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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.
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