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91.
Experimental nonequilibrium surface tension measurements of 1–9 nonanediol solutions obtained by the oscillating-jet method have been interpreted in terms of our theoretical predictions derived for a mixed-controlled adsorption kinetics of the surfactant. The surface tension values have been calculated from the Szyszkowski equation using the Langmuir model of surfactant adsorption. Our theoretical results, obtained by a numerical solution of the adsorption equations, agree well with experimental data giving a value of the kinetics Szyszkowski constant very similar to the thermodynamic equilibrium value determined from experimental measurements of the static surface tension of 1–9 nonanediol solutions of various concentration. The approximate kinetic equation derived by P. Joos, G. Bleys, and G. Petre (J. Chim. Phys.79, 387 (1982)) for purely barrier-controlled adsorption proved to be less accurate. 相似文献
92.
A hybrid PDMS/glass microfluidic system for evaluation of the efficiency of photodynamic therapy is presented. 5-aminolevulinic acid (ALA) was used as a precursor of photosensitizer. The geometry of the microdevice presented in this paper enables to test different concentrations of the photosensitizer in a single assay. The viability of the A549 cells was determined 24 h after PDT procedure (irradiation with light which induced a photosensitizer accumulated in carcinoma cells, λ = 625 nm). The presented results confirmed the possibility to perform the photodynamic therapy process in vitro in microscale and the possibility to assess its effectiveness. Moreover, because two identical microstructures on a single chip were performed, the microchip can be used for examination simultaneously various cell lines (carcinoma and normal) or various photosensitizers. 相似文献
93.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献
94.
Lezak E Kulinski Z Masirek R Piorkowska E Pracella M Gadzinowska K 《Macromolecular bioscience》2008,8(12):1190-1200
Green composites of PLA with micropowders derived from agricultural by-products such as oat husks, cocoa shells, and apple solids that remain after pressing have been prepared by melt mixing. The thermal and mechanical properties of the composites, including the effect of matrix crystallization and plasticization with poly(propylene glycol), have been studied. All fillers nucleated PLA crystallization and decreased the cold-crystallization temperature. They also affected the mechanical properties of the compositions, increasing the modulus of elasticity but decreasing the elongation at break and tensile impact strength although with few exceptions. Plasticization of the PLA matrix improved the ductility of the composites. 相似文献
95.
This supplement contains 222 (angel number) further papers on false or unconfirmed ferroelectric properties in single crystals, ceramics and polymers and only concerns bulk materials. Thus, the number of such papers has reached huge value 727. The papers marked in red have drastically broken the principles of symmetry because they reported the existence of ferroelectricity in crystals without the polar axis. 相似文献
96.
Vadim V. Ilyushin Zbigniew Kisiel Heinrich Mäder 《Journal of Molecular Spectroscopy》2010,259(1):26-12194
A new program is described for fitting rotation-torsion energy levels in molecules like toluene, in which the frame (C6H5) has C2v symmetry and the methyl top has C3v symmetry, i.e., for molecules where the internal rotation barrier is expanded in cos6nα, where α is the internal rotation angle and n = 1,2,…. The program is based on the theoretical framework developed by Sørensen and Pedersen in their application of the Longuet-Higgins permutation-inversion group G12 to the microwave spectrum of CH3NO2. It is specifically designed for sixfold barrier molecules, and allows the user to select almost any symmetry-allowed torsion-rotation term for inclusion in the fitting Hamiltonian. This program leads to a very successful fit of transitions in the microwave spectrum of toluene characterized by J ? 30, Ka ? 12, and by the free-rotor quantum number ∣m∣ ? 3. In these fits we included both published and rather extensive unpublished new measurements, for which fits using other torsion-rotation programs have not been very successful. The fit presented here uses 28 parameters to give an overall standard deviation of 7.4 kHz for 372 line frequencies, and results in a much improved value for the sixfold barrier for toluene, V6 = 13.832068(3) cal mol−1. 相似文献
97.
98.
D. Kamińska A. Gajos E. Czerwiński D. Alfs T. Bednarski P. Białas C. Curceanu K. Dulski B. Głowacz N. Gupta-Sharma M. Gorgol B. C. Hiesmayr B. Jasińska G. Korcyl P. Kowalski W. Krzemień N. Krawczyk E. Kubicz M. Mohammed Sz. Niedźwiecki M. Pawlik-Niedźwiecka L. Raczyński Z. Rudy M. Silarski A. Wieczorek W. Wiślicki B. Zgardzińska M. Zieliński P. Moskal 《The European Physical Journal C - Particles and Fields》2016,76(8):445
99.
100.
Two types of biomolecules were tested in the comparison of usefulness of two ways of formation of the intermediate layers at electrodes: a 20‐nucleotide DNA sequence and glucose oxidase. Chronocoulometric, amperometric, electrochemical impedance and PM‐IRRAS experiments proved that the layers obtained by electroreduction of diazonium salts are much more stable and more efficient in the accumulation of biomolecules compared to layers obtained by self‐assembling of appropriate thiols. 相似文献