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91.
Takahashi M Satou T Ohashi M Hayashi S Sadamoto K Koike K 《Natural product communications》2011,6(11):1769-1774
Essential oils have traditionally been used for decades to alleviate the symptoms of various mental problems. In terms of anxiolytic-like properties, lavender oil is probably the most commonly used and best-studied essential oil. Although there is compositional variance among the oils extracted from different origins, there have been few studies performed to date to investigate how these differences affect the expression of anxiolytic-like activity. This paper discusses the interspecies differences and contributions of the main constituents in the expression of anxiolytic-like effects upon inhalation, as assessed in mice by the elevated-plus maze test, by comparing the essential oils from six different species of Lavandula. The results showed qualitative and quantitative variations in the tested oils, which results in significant differences in their anxiolytic-like activities. Our findings also suggest that linalyl acetate (LA) works synergistically with linalool (LO) and that the presence of both LA and LO is essential for the whole oil to work as an inhaled anti-anxiety agent. 相似文献
92.
The effect of protonation to formanilides was studied by measurements of 13C-NMR chemical shifts in CDCl3 and methanesulfonic acid. It was found that the 13C shift of the ring carbon, to which the amide group is attached, exhibits an upfield shift by the protonation, whereas the peaks of the rest of ring carbons and carbonyl carbon shift downfield. The protonation-induced shifts of the ring carbons were found to be roughly correlated with the differences of the total electron densities between formanilides and their monocations. From the comparison between the protonation-induced shifts and the differences of the total electron densities at the carbons, especially at the carbonyl carbon, it is suggested that N-protonation is partly involved, although O-protonation seems to be dominant. 相似文献
93.
Chikara Shito Keitaro Okamoto Yuki Sato Ryuji Watanabe Tomonori Ohashi Kazuhiro Fuchizaki 《高压研究》2013,33(3):499-508
ABSTRACTHigh pressure hydrous phases with distorted rutile-type structure have attracted much interest as potential water reservoirs in the Earth’s mantle. An in-situ X-ray diffraction study of β-CrOOH was performed at high pressures of up to 6.2?GPa and high-temperatures of up to 700?K in order to clarify the temperature effect on compression behaviors of β-CrOOH. The P-V-T data fitted to a Birch–Murnaghan equation of state yielded the following results: isothermal bulk modulus KT0?=?191(4)?GPa, temperature derivative (?KT/?T)P?=??0.04(2)?GPa?K?1, and volumetric thermal expansion coefficient α?=?3.3(2)?×?10?5?K?1. In this study, at 300?K, the a-axis became less compressible at pressures above 1–2?GPa. We found that the pressure where the slopes of a/b and a/c ratios turned positive increased with temperature. This is the first experimental study indicating the temperature dependence of the change in the axial compressibility in distorted rutile-type M3+OOH. 相似文献
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96.
A manifold is described which permits the analysis of less than 1 ml of sample solution. Water- and air-compensation methods for the introduction of the carrier stream into the nebulizer are effective in obtaining sensitive and reproducible measurements of magnesium, but air-compensation gives higher peak responses. 相似文献
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98.
Akira Matsumoto Shigeyuki Yokoyama Tetsuro Khono Masayoshi Oiwa 《Journal of Polymer Science.Polymer Physics》1977,15(1):127-136
Studies on gelation in the radical polymerization of diallyl dicarboxylates have been conducted by Simpson,9,11 Gordon,10 and Oiwa.13 However, the results obtained have not always been consistent and are still far from full elucidations. In this paper, the gel point in the polymerization of diallyl aromatic dicarboxylates, including diallyl phthalate (DAP), diallyl isophthalate (DAI), and diallyl terephthalate (DAT) is experimentally reexamined in detail and discussed according to Gordon's theory; the discrepancy between actual and theoretical gel point conversion was quite large and was enhanced in the order DAT > DAI > DAP. Moreover, from detailed inquiry into the primary chain length of the prepolymer it is suggested that the intramolecular chain transfer reaction plays an important role in the polymerization of diallyl ester accompanying the intramolecular cyclization reaction. The polydispersity coefficient (P w,0/P n,0) of the initial prepolymer of DAP is also estimated to be 2.0 from the extrapolation of P w/P n to zero conversion. 相似文献
99.
An apparatus and the procedure for cellulose acetate isoelectric focusing were refined and optimized for routine use in clinical laboratories. The space in the electrophoretic chamber was minimized to maintain high humidity during the run. The water content of the thin cellulose acetate membranes in the chamber was well controlled during isoelectric focusing and the effect of atmospheric carbon dioxide was also excluded. The temperature of the membranes was kept below 2 degrees C, even under conditions of high electric field strength for faster isoelectric focusing of high-molecular-weight proteins. No special training was required for technicians in clinical laboratories to obtain reproducible isoelectric profiles of human serum proteins. 相似文献
100.