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101.
Yoshimune Nonomura Keisuke Nakayama Yuki Aoki Atsuhiro Fujimori 《Journal of colloid and interface science》2009,339(1):222-229
Dietary lipids are solubilized in bile acid micelles in the small intestine. In the present study, we investigate the phase behavior of bile acid/model rapeseed oil (or model beef tallow)/water systems to predict interfacial phenomena during consumption of a variety of foods. The structures of molecular assemblies are identified based on polarizing microscope images, wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS). The results of in vitro tests suggest that an increase in the intake of model rapeseed oil causes the formation of multi-lamellar vesicles and lamellar liquid crystals. The molecules in the lamellar liquid crystal are formed highly ordered layer structure with the spacing of 8.8 nm along the c-axis, while monoclinic packed structure is constructed as two-dimensional structure in ab-plane due to bulky molecular structures of bile acid and unsaturated fatty acid. When the model beef tallow composition in the model system is more than several wt.%, stearic acid crystals are extracted. Moreover, bicarbonate ions are important ingredients to solubilize >10 wt.% of the model lipids. These phase transitions might be induced by the addition of dietary lipids in vivo during the consumption of oil or meat. Our findings are significant for understanding the lipid absorption process in the small intestine, and for developing medical and healthcare products. 相似文献
102.
In this paper, we shall prove that a projective‐planar (resp., toroidal) triangulation G has K6 as a minor if and only if G has no quadrangulation isomorphic to K4 (resp., K5 ) as a subgraph. As an application of the theorems, we can prove that Hadwiger's conjecture is true for projective‐planar and toroidal triangulations. © 2009 Wiley Periodicals, Inc. J Graph Theory 60: 302‐312, 2009 相似文献
103.
Rational synthesis of A(2)B-type meso-arylsubporphyrins has been accomplished by the condensation of triethylamine-tri-N-tripyrromethene-borane with acid chlorides. These subporphyrins are useful for evaluations of the intrinsic substituent effects and the influences of substitution patterns, A(3)-type versus A(2)B-type substitution. 相似文献
104.
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106.
Let M be a map on a surface F
2. A geometric realization of M is an embedding of F
2 into a Euclidian 3-space ℝ3 with no self-intersection such that each face of M is a flat polygon. In Bonnington and Nakamoto (Discrete Comput. Geom. 40:141–157, 2008), it has been proved that every triangulation G on the projective plane has a face f such that the triangulation G−f on the M?bius band obtained from G by removing the interior of f has a geometric realization. In this paper, we shall characterize such a face f of G. 相似文献
107.
Fujimori A Taguchi M Hakozaki S Kamishima K Ochiai B 《Langmuir : the ACS journal of surfaces and colloids》2012,28(29):10830-10837
Surface complexing (i.e., metal-bridged polymerization in this study) of a three-armed amphiphilic compound with metal-scavenging properties has been investigated using the surface pressure-area (π-A) isotherms of a Langmuir monolayer from the subphase. Inductively coupled plasma mass spectrometry (ICP-MS) was also carried out on eluted solutions from corresponding multilayers of the solid. Furthermore, the molecular arrangement and surface morphology of organized molecular films of the resultant comb polymer were estimated by in-plane and out-of-plane X-ray diffraction (XRD) and by atomic force microscopy. From an analysis of the wide-angle X-ray diffraction of the corresponding monomer in the bulk, the long hydrocarbon chains are observed to pack hexagonally in the solid state. Compared to their monolayer on distilled water as the subphase, a polymerized monolayer on a buffer solution containing Cd(2+) ions is remarkably expanded at 15 °C. From ICP-MS and IR measurements, it is found that this monolayer stoichiometrically contains Cd(2+) ions on the -SH group. It is found by XRD that highly ordered layer structures and regular 2D lattices are constructed in the organized molecular films of the Cd-bridged comb polymer. Furthermore, the surface morphology of Langmuir-Blodgett films fabricated from the monolayers on a buffer solution containing Cd(2+) and Pd(2+) shows flat and smooth domains upon metal scavenging and polymerization. 相似文献
108.
5,10,15‐Tris(pentafluorophenyl)tetrapyrromethane was efficiently prepared through a route involving stepwise diaroylation of 5‐pentafluorophenyldipyrromethane. A2B6‐type [36]octaphyrins were prepared by the cross condensation of the tetrapyrromethane with aryl aldehydes in moderate yields. A2B6‐type [36]octaphyrins bearing 2,4,6‐trifluorophenyl, 2,6‐dichlorophenyl, and phenyl substituents underwent CuII‐metalation‐induced fragmentation to give two molecules of AB3‐type CuII porphyrins. A2B6‐type [36]octaphyrin bearing 3‐thienyl substituents underwent thermal N‐thienyl fusion reactions to provide a modestly aromatic [38]octaphyrin, which, upon treatment with MnO2, underwent further N‐thienyl fusion and subsequent oxidation to give a nonaromatic doubly N‐thienyl fused [36]octaphyrin. 相似文献
109.
110.
Bahng HW Kim P Sung YM Maeda C Osuka A Kim D 《Chemical communications (Cambridge, England)》2012,48(35):4181-4183
It has been demonstrated that the direction and magnitude of transition dipole moments, and hence rates in the excitation energy hopping in the self-assembled porphyrin boxes can be tuned by insertion of ethynyl groups as well as the dielectric constant of solvent. 相似文献