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21.
The amounts of d-limonene, ethanol and indomethacin (IMC) which were transferred from aqueous gel ointments to the skin were determined in rats. The concentration of IMC in the skin correlated well with the plasma concentration of IMC percutaneously absorbed from the gel ointment. The increase of d-limonene concentration in the gel ointments was directly proportional to the accumulation of ethanol in the skin. The amount of ethanol in the skin was closely associated with the percutaneous absorption of IMC. As a possible mechanism for enhancement action of d-limonene and ethanol, it was considered that, at first, d-limonene penetrates into the skin under coexistence with ethanol and may change the barrier structure of the stratum corneum. The transfer of ethanol to the skin is thereby enhanced under the coexistence of d-limonene in the skin. Thus, the permeation of IMC can be promoted due to its affinity with ethanol. 相似文献
22.
Kentaro Suzuki Taro Toyota Katsuhiko Sato Masakazu Iwasaka Shoogo Ueno Tadashi Sugawara 《Chemical physics letters》2007,440(4-6):286-290
Collagen-containing tubular giant vesicles (Col–tGVs) under a high static magnetic field were found to constitute characteristic curved structures (e.g. circular, 8-figure, and hairpin-loop), which were sustained by polymerization of collagen units inside the tGV. We ascribed the formation of these structures to the elasticity of the tGV and to the competing diamagnetic anisotropies between collagen and the tGV. These curved structures can be well expressed by the equation of elastica. 相似文献
23.
Separation of fulvic acid from soil extracts based on ion-pair formation with a cationic surfactant.
Masami Fukushima Atsunori Kikuchi Kenji Tatsumi Fumiko Tanaka 《Analytical sciences》2006,22(2):229-233
A novel method for separating fulvic acid (FA) from soil extracts is proposed. The FA, defined as the acid-soluble fraction of an alkaline extract of soil, was separated based on the precipitation of an ion-pair with a cationic surfactant, such as domiphen bromide. The precipitate was dissolved in aqueous HCl to produce H+ -type FA and a surfactant chloride (SUR-Cl). SUR-Cl, in the aqueous solution, was removed by extraction with CHCl3. After the aqueous phase was passed through a cation-exchanger (H+ -type), H+ -type FA (FA-SUR) was obtained as a powder by lyophylization. The chemical characteristics of FA-SUR were compared with an FA sample separated according to the method of the International Humic Substances Society using a DAX-8 resin (FA-DAX). The oxygen content, O/C atomic ratio and total acidity of the FA-SUR were significantly larger than the corresponding values for FA-DAX. The solid-state CPMS 13C NMR spectra indicated that the higher oxygen content of the FA-SUR could be due to alcoholic hydroxyl groups and polysaccharides as well as carboxylic groups. These results show that FA-SUR is more polar and hydrophilic than FA-DAX. 相似文献
24.
Hirotaka Okamoto Tadashi Inoue Kunihiro Osaki 《Journal of Polymer Science.Polymer Physics》1995,33(3):417-424
The complex Young's modulus, E*(ω), and the complex strain-optical coefficient, O*(ω), which is the ratio of the birefringence to the strain, were measured for polyisoprene (PIP) over a frequency range of 1 ~ 130 Hz and a temperature range of 22 ~ ?100°C. The imaginary part of O*, O″, was positive at low frequencies and negative at high frequencies. The real part, O′, was always positive and showed a maximum. The complicated behavior of O* could be understood by the assumption that E* = ER* + EG* and O* = CRER* + CGEG*, where ER* and EG* were complex quantities and CR and CG were constants. The CR value, equal to the ordinary stress-optical coefficient measured in the rubbery plateau zone, was 2.0 × 10?9 Pa?1. The CG value, defined as the ratio O″/E″ in the glassy zone, was ?1.1 × 10?11 Pa?1. The EG*, which was the major component of E* in the glassy zone, showed almost the same frequency dependence as that of polystyrene and polycarbonate. The ER*, which was dominant in the rubbery zone, was described well by the bead-spring theory. The temperature dependence of the EG* was stronger than that of the ER*. This difference caused the breakdown of the thermorheological simplicity for E* and O* around the glass-to-rubber transition zone. © 1995 John Wiley & Sons, Inc. 相似文献
25.
Let m be an integer with m3. Let K and K be perfect fields of characteristic p and p such that (p,m)=1 and (p,m)=1, respectively. Moreover let A and A be algebraic function fields over K and K defined by xm+ym=a(0, ak) and xm+ym=a(a0 ak), respectively. Put g=(m–1)(m–2)/2. Denote by M(K,p,a) and M(K,p,a) the Hasse-Witt matrices of A and A with respect to the canonical bases of holomorphic differentials. Then we show that if p+p0(mod.m) then rank M(K,p,a)+rank M(K,p,a)=g and if pp1 (mod.m) then rank M(K,p,a)=rank M(K,p,a). 相似文献
26.
Chowdhury Wasimul Q. Idehara Kenji Maeda Isamu Umeda Fusako Yagi Kiyohito Miura Yoshiharu Mizoguchi Tadashi 《Applied biochemistry and biotechnology》1996,57(1):361-366
Applied Biochemistry and Biotechnology - A marine photosynthetic bacterium,Rhodopseudomonas sp. strain W-1S, accumulated polyhydroxybutyrate (PHB) to 56% of the dry cell weight under microaerobic... 相似文献
27.
28.
The enantiodifferentiating [4+4] photocyclodimerization of anthracenecarboxylic acid (AC) mediated by native, mono- and di-3,6-anhydro-γ-cyclodextrins was investigated in both aqueous solution and solid-state. The solid-state photolyses gave inherently disfavored head-to-head photodimers in much higher chemical and optical yields than in the aqueous solution. 相似文献
29.
Takeshi Ishijima Yoshiki Mizumori Kenji Kikuchi Atsushi Suzuki Takuji Okaya 《Colloid and polymer science》2005,283(7):799-804
Polymerization of vinyl acetate (VAc) in various fatty acids (carbon numbers 4–18) was carried out. Chain transfer constants to the acids were determined to be 20–35×10–4, from which the constant to a methylene group was obtained to be 0.73×10–4. Viscometry in aqueous solution of derived poly (vinyl alcohol) (PVA) showed the usual behavior in terms of Huggins constant obtained by the Schulz–Blaschkes equation for PVAs derived from fatty acid systems lower than hexadecanoic acid. PVA derived from octadecanoic acid system showed abnormality, indicating association of alkyl groups. Contact angles on surfaces of PVAs cast from aqueous solutions were measured. While those of PVA derived from lower acid systems were 62°, those of PVAs derived from higher aids were higher and increased to 92° with increase in carbon number to octadecanoic acid. Alkyl groups in the PVAs were estimated to appear on the surfaces. Surface tension of aqueous solution of the PVA derived from octadecanoic acid showed high surface activity, and depended on pH of the solution, indicating the presence and cleavage of lactone ring at the combined portion between PVA and the acid. 相似文献
30.
The Longuet-Higgins and Pople type SCF MO theory was applied to the all-valence-electron systems of several -type radicals and their g-tensors were theoretically calculated with the Stone's equation. Principal values or diagonalyzed g-tensors were obtained and compared with experimental values in ESR spectra. 相似文献