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111.
The microphase adsorption-spectral correction (MPASC) technique was described and applied to the study of the interactions of fluorinated surfactants such as potassium perfluorooctanesulfonate (PFOS) and potassium perfluorobutanesulfonate (PFBS) with human serum albumin (HSA). Sodium octanesulfonate (SOS) was also studied as non-fluorinated surfactant. The aggregation of PFOS, PFBS and SOS obeys the Langmuir monolayer adsorption. The results show that the adsorption ratios of surfactants to HSA are PFOS:HSA = 120:1, PFBS:HSA = 205:1 and SOS:HSA = 18:1. The adsorption constants are KPFOS-HSA = 5.01 × 103, KPFBS-HSA = 9.79 × 102 and KSOS-HSA = 4.03 × 103. The detection limits are 2.7 mg/L for BSA using PFOS, 3.1 mg/L using PFBS and 3.1 mg/L using SOS. It was found that fluorinated surfactant exhibited stronger interaction with protein than hydrogenated one, and fluorinated surfactant with long hydrophobic chain exhibited stronger interaction with protein than that with short hydrophobic chain. 相似文献
112.
Larisa P. Demyanova 《Journal of fluorine chemistry》2009,130(9):799-805
The effect of fluorination on silicate and alumino-silicate minerals has been investigated, in particular on the lepidolite [K(Li,Al)3 [Si3AlO10] (F,OH)2] of the mica-type. The fluorination techniques included direct F2-gas and cold radio-frequency-plasma involving c-C4F8 or O2/CF4 mixtures. The modifications of the surface properties have been followed mostly by XPS. Depending of the fluorination route used, either a reactive etching process involving M-F bonding occurs (direct F2-gas; O2-CF4 rf-plasma), or a carbon fluoride deposition takes place (c-C4F8 rf-plasma). 相似文献
113.
Ping Liu 《Journal of organometallic chemistry》2009,694(14):2290-2647
Bis(imino)pyridine palladium(II) complexes 3-6 were synthesized by two different methods. The structure of complexes 3 and 4 has been confirmed by X-ray structure analysis. The catalytic studies show that bis(imino)pyridine palladium(II) complexes are highly efficient catalysts in the Suzuki-Miyaura reaction and the complex 4 was used to catalyze the synthesis of fluorinated liquid crystalline compounds via Suzuki coupling reaction. 相似文献
114.
Five new block copoly(imide siloxane)s have been prepared by reacting two different diamines, 4,4″-bis(p-aminophenoxy)-3,3″-trifluoromethyl terphenyl (APTTFT) and amino-propyl terminated polydimethylsiloxane (APPS), separately with 4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride); BPADA. The reactions were conducted by a two pot solution imidization technique. The diamine APTTFT and the dianhydride BPADA composed the hard block segment while APPS and BPADA composed the soft block segment. The soft and hard blocks of different block lengths were generated by different stoichiometric imbalance in two different flasks and the final polymers were obtained by reacting both the blocks together. Different block copoly(imide siloxane)s were prepared on increasing the hard block lengths (DP) from 7 to 12, 18, 23 and 28 and the soft block lengths (DP) from 4 to 6, 8, 10 and 12, respectively. The resulting polymers have been well characterized by NMR, DSC and DMA techniques. The properties of the block copolymers were compared with the analogous random copolymers and homopolyimide prepared without APPS. 相似文献
115.
116.
Vronique Peyre 《Current Opinion in Colloid & Interface Science》2009,14(5):305-314
Mixtures of hydrogenated and fluorinated surfactants are known to form either mixed or segregated micelles: the conclusions are much dependant on the precision of the experimental measurements and on the model used for interpretation. Recently, mixed surfactant solutions were probed at the micellar or molecular level by SANS, fluorescence or NMR. It leads to an intermediate structure for the mixed micelles with an intramicellar segregation of the fluorinated and hydrogenated surfactant.This intramicellar segregation was also observed in a variety of more complex systems which are rapidly surveyed in the second part. 相似文献
117.
Hoda K Nakahara H Nakamura S Nagadome S Sugihara G Yoshino N Shibata O 《Colloids and surfaces. B, Biointerfaces》2006,47(2):165-175
Surface pressure–area (π–A), surface potential–area (ΔV–A), and dipole moment–area (μ–A) isotherms were obtained for the Langmuir monolayer of two fluorinated-hydrogenated hybrid amphiphiles (sodium phenyl 1-[(4-perfluorohexyl)-phenyl]-1-hexylphosphate (F6PH5PPhNa) and (sodium phenyl 1-[(4-perfluorooctyl)-phenyl]-1-hexylphosphate (F8PH5PPhNa)), DPPC and their two-component systems at the air/water interface. Monolayers spread on 0.02 M Tris buffer solution (pH 7.4) with 0.13 M NaCl at 298.2 K were investigated by the Wilhelmy method, ionizing electrode method and fluorescence microscopy. Moreover, the miscibility of two components was examined by plotting the variation of the molecular area and the surface potential as a function of the molar fraction for the fluorinated-hydrogenated hybrid amphiphiles on the basis of the additivity rule. The miscibility of the monlayers was also examined by construction of two-dimensional phase diagrams. Furthermore, assuming the regular surface mixture, the Joos equation for analysis of the collapse pressure of two-component monolayers allowed calculation of the interaction parameter (ξ) and the interaction energy (−Δ) between the fluorinated-hydrogenated hybrid amphiphiles and DPPC. The observations by a fluorescence microscopy also supported our interpretation as for the miscibility in the monolayer state. Comparing the monolayer behavior between the two binary systems, no remarkable difference was found among various aspects. Among the two combinations, the mole fraction dependence in monlayer properties was commonly classified into two ranges: 0 ≤ X ≤ 0.3 and 0.3 < X ≤ 1. Dependence of the chain length of fluorinated part was reflected for the molecular packing and surface potential. 相似文献
118.
Thomas Braun Verena Schorlemer Beate Neumann Hans-Georg Stammler 《Journal of fluorine chemistry》2006,127(3):367-372
[PdMe2(dcpm)] (1) reacts with 2,4,6-trifluoropyrimidine in the presence of water to give the palladium derivative [PdMe{4-C4N2F2H(O)}(dcpm)] (2). When additional triethylamine is present complex [PdMe(2-OC4N2F2H)(dcpm)] (4) in addition to 2 is formed. Compound 2 converts slowly into the binuclear complex [Pd{4-C4N2F2H(O)}(μ-dcpm)]2 (5). The molecular structure of 5 was determined by X-ray crystallography. The palladium-palladium distance is 2.5898(3) Å. 相似文献
119.
Maribel Arroyo Sylvain Bernès Norma Calixto Carina Gómez 《Journal of fluorine chemistry》2006,127(1):22-28
A series of three new trithioether compounds containing fluorinated phenyl moieties, 1,3,5-(CH2SRf)3-2,4,6-(CH3)3C6, Rf = C6F5 (1), 4-HC6F4 (2), or 2-FC6H4 (3), were prepared by treatment of 1,3,5-(CH2Br)3-2,4,6-(CH3)3C6 with the corresponding Pb(SC6F5)2 or NaSRf. The new structures were verified by elemental analyses, IR, 1H NMR, 19F NMR spectroscopies, and mass spectra. The single crystal X-ray diffraction studies of 1-3 show a similar cis,trans,trans-conformation for the three fluorophenylthiomethyl groups attached to the central benzene ring with all dihedral angles between planes of central ring and external rings close to 0°, giving flat molecules. Comparing, 1-3 with closely related tripodal molecules built-up on 2,4,6-trimethylbenzene, arrangement of one SR group respect to others seems to be defined by the nature of the R substituent. Then in the case of 1-3, a parallel arrangement of rings is favored over an orthogonal one, which would bring the ortho-F atoms close to H atoms of the methylene groups. 相似文献
120.
Previous studies describe derivatization of metal ions followed by analysis using gas chromatography, usually on packed columns. In many of these studies, stable and volatile derivatives were formed using fluorinated β‐diketonate reagents. This paper extends previous work by investigating separations of the derivatives on small‐diameter capillary gas chromatography columns and exploring on‐fiber, solid‐phase microextraction derivatization techniques for beryllium. The β‐diketonate used for these studies was 1,1,1,2,2,6,6,7,7,7‐decafluoro‐3,5‐heptanedione. Derivatization of lanthanides also required addition of a neutral donor, dibutyl sulfoxide, in addition to 1,1,1,2,2,6,6,7,7,7‐decafluoro‐3,5‐heptanedione. Unoptimized separations on a 100‐μm i.d. capillary column proved capable of rapid separations (within 15 min) of lanthanide derivatives that are adjacent to one another in the periodic table. Full‐scan mass spectra were obtained from derivatives containing 5 ng of each lanthanide. Studies also developed a simple on‐fiber solid‐phase microextraction derivatization of beryllium. Beryllium could be analyzed in the presence of other alkali earth elements (Ba(II) and Sr(II)) without interference. Extension of the general approach was demonstrated for several additional elements (i.e. Cu(II), Cr(III), and Ga(III)). 相似文献