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61.
62.
63.
Roy Mathias 《Numerische Mathematik》1992,63(1):213-226
LetM
n
denote the space ofn×n matrices. GivenX, ZM
n
define
相似文献
64.
65.
Mathias JM 《OR manager》1992,8(3):1, 20-1, 22
OR Manager is examining sacred cows in the OR--practices blessed by time that do not necessarily improve patient outcomes. We'll give you the information you need to decide whether these sacred cows should be retired. 相似文献
66.
Rancan F Wiehe A Nöbel M Senge MO Omari SA Böhm F John M Röder B 《Journal of photochemistry and photobiology. B, Biology》2005,78(1):17-28
The search for new efficient sensitizers for photodynamic therapy (PDT) points to improve photophysical properties like absorption in the red region and singlet oxygen quantum yield as well as to control the localization of the sensitizer within the tumour cell. Depending on their physicochemical properties and their uptake mechanism, sensitizers can reach different intracellular concentrations and localize in different subcellular compartments. Moreover, the preferential localization of a sensitizer in target organelles, like mitochondria or lysosomes, could determine the cell death mechanism after PDT. This study aimed to investigate the influence of substitutions on dihydroxychlorins with regard to intracellular uptake, subcellular localization and cell death pathway. Moreover, the effect of a liposome-based delivery system was tested. The intracellular uptake was found to be strictly dependent on the sensitizer molecular structure and the means of its delivery. The most polar sensitizer in this study (compound 3) had, depending on incubation time, an intracellular concentration 2-8 times higher than the unsubstituted chlorin 1. All investigated photosensitizers localize predominantly in lysosomes but after longer incubation times weak fluorescence intensity was also detected in mitochondria and Golgi apparatus. The cell death pathway was found to be influenced by the sensitizer intracellular concentration and the applied light doses. In general, the increasing amphiphilicity of the sensitizer molecules is correlated with an increased sensitizer uptake and an increased rate of necrotic cells after irradiation. 相似文献
67.
Bianca S. Shemper A. Ersin Acar Lon J. Mathias 《Journal of polymer science. Part A, Polymer chemistry》2002,40(3):334-343
The copper‐catalyzed atom transfer radical polymerization (ATRP) of poly(propylene glycol) methacrylate (PPGM) in solution to produce linear and starlike polymers is reported, using methylethyl ketone as the solvent and a temperature of 80 °C. The ATRP system used was efficient for polymerization of the functionalized monomer without protecting hydroxyl end groups of monomer. The polymerizations were consistent with “living” or controlled processes, as revealed by the linear evolution of molecular weight with conversion. Increasing the [M]0:[I]0 ratio resulted in increasing molecular weights, whereas the polydispersity indices remained low (Mw/Mn < 1.4) even at high conversion. Decreasing the [CuBr]0:[I]0 ratio resulted in lower conversions, slightly larger polydispersities, and decreased molecular weights, likely resulting from a lower initiation efficiency. Polymers were characterized by 1H and 13C NMR; molecular weights of polymers with low degrees of polymerization were estimated by end‐group analysis from 13C NMR spectra obtained using distortionless enhancement by polarization transfer and the gated decoupling techniques. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 334–343, 2002 相似文献
68.
We report laser photoelectron spectra of the doubly negatively charged fullerenes C(76) (2-), C(78) (2-), and C(84) (2-) at 2.33, 3.49, and 4.66 eV photon energy. From these spectra, second electron affinities and vertical detachment energies, as well as estimates for the repulsive Coulomb barriers are obtained. These results are discussed in the context of electrostatic models. They reveal that fullerenes are similar to conducting spheres, with electronic properties scaling with their size. The experimental spectra are compared with the accessible excited states of the respective singly charged product ions calculated in the framework of time dependent density functional theory. 相似文献
69.
Dr. David van Gerven Stefan Sutorius Dr. Jrn Bruns Prof. Mathias S. Wickleder 《ChemistryOpen》2022,11(11)
The reaction of elemental iodine and SO3 in a sealed glass ampoule yielded a turquoise‐colored solution. At temperatures below 7 °C, deep red crystals of (I4)[S6O19] grow. With the addition of B2O3 and pyridine‐SO3 complex red crystals of (I4)[B(S2O7)2]2 can be obtained after heating the mixture to 120 °C. The combination of an (I4)2+ cation with oxoanions has previously not been observed. Both anions have a significant but different influence on the structural properties of the (I4)2+ cation. 相似文献
70.
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