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191.
Yasuhiro Ono Michiko Nakaya Tsuyoshi Kajitani Tamotsu Sugawara Noriko Watanabe Hiroyuki Shiraishi Ryuichi Komatsu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1413-1415
The title compounds, LiKB4O7 and LiRbB4O7, are newly developed non‐linear optical crystals containing two kinds of anionic groups, namely (B3O8)7? and (B5O10)5?. The (B3O8)7? groups form infinite spiral chains parallel to the [100] direction, which are interconnected by sharing O atoms with (B5O10)5? groups. 相似文献
192.
Kumon M Suzuki M Kusai A Yonemochi E Terada K 《Chemical & pharmaceutical bulletin》2006,54(11):1508-1514
The effect of lactose carrier surface property on the inhalation profile of dry powder inhaler (DPI) was evaluated using a micronized drug (Compound A) by inverse gas chromatography (IGC). Mechanofusion with magnesium stearate (Mg-St) or sucrose stearate increased the fine particle fraction (FPF), considered to be due to decrease in the interaction between Compound A and the lactose carrier. The effect of Compound A concentration on FPF was smaller in mechanofusion-processed lactose compared to intact lactose, especially when processed with Mg-St. The relationship between the IGC parameters of the lactose and FPF was also investigated. FPF increased as both the dispersive component of the surface energy and acidity similarity between the lactose carriers and Compound A increased. Although further investigation is necessary, it could be suggested that acidity similarity decreases the interaction between Compound A and lactose, thus contributing to the increase in the FPF. In conclusion, (1) mechanofusion with Mg-St or sucrose stearate could be an effective method to improve FPF of a DPI drug formulation; (2) IGC would be a valuable method to investigate the interaction between a drug and the DPI carrier; and (3) a relationship between surface acidity and inhalation profile was suggested. 相似文献
193.
Ono M Masuoka C Koto M Tateishi M Komatsu H Kobayashi H Igoshi K Ito Y Okawa M Nohara T 《Chemical & pharmaceutical bulletin》2002,50(10):1416-1417
A new ortho-benzoyloxyphenyl acetic acid ester, called vaccihein A (1), was isolated from the fruit of rabbiteye blueberry (Vaccinium ashei). The chemical structure was determined on the basis of spectroscopic data. Compound 1 had antioxidative activity using the ferric thiocyanate method. In addition, 1 showed a scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl. 相似文献
194.
Doris?FiebigEmail author Ulf-Rainer?Fiebig Michiko?Yuri 《Israel Journal of Mathematics》2002,131(1):221-257
We give a general definition of the topological pressureP
top
(f, S) for continuous real valued functionsf: X→ℝ on transitive countable state Markov shifts (X, S). A variational principle holds for functions satisfying a mild distortion property. We introduce a new notion of Z-recurrent
functions. Given any such functionf, we show a general method how to obtain tight sequences of invariant probability measures supported on periodic points such
that a weak accumulation pointμ is an equilibrium state forf if and only if εf
−
dμ<∞. We discuss some conditions that ensure this integrability. As an application we obtain the Gauss measure as a weak limit
of measures supported on periodic points. 相似文献
195.
196.
Hiizu Iwamura Michiko Iwamura Mamoru Imanari Makoto Takeuchi 《Tetrahedron letters》1973,14(26):2325-2328
197.
Ono M Tateishi M Masuoka C Kobayashi H Igoshi K Komatsu H Ito Y Okawa M Nohara T 《Chemical & pharmaceutical bulletin》2003,51(2):200-202
A new triterpene glucosyl ester, rubusside A, has been isolated from the fruit of the blackberry (Rubus allegheniensis PORT.) along with a known triterpene glucosyl ester, niga-ichigoside F1. The chemical structure of rubusside A was determined on the basis of spectroscopic data as well as chemical evidence. 相似文献
198.
Summary For estimating the values corresponding to the oxygen defects in high Tc superconducting oxides, iodometry has been applied for the determination of Cu3+ and Cu2+. The presence of Bi or Pb causes some difficulty in the identification of the end point of this titration, because of the formation of iodine complexes. Therefore, chlorine generation from HCl and iodometry was applied for the determination of Bi5+ or Pb4+ in the oxides, and for the additional determination of Cu3+, O2 generation was used together with Cl2 generation for Bi5+ or Pb4+. 相似文献
199.
200.
Dioctadecyldimethylammonium chloride (DOAC) was completely dehydrated under high vacuum and at a temperature above its transition temperature (96.7°C) which was first discovered by us. Thermoanalytical studies on DOAC-water systems indicate that two successive phase changes of coagel → gel and gel → liquid crystal appear due to the increasing structural disorders of polar head groups and hydrocarbon chains, respectively. Furthermore, it is revealed that three types of water exist, i.e., bound, intermediate and free. On the basis of a bilayer-lamellar structure model, a predominant role of the intermediate water in these transitions is pointed out. 相似文献