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991.
Summary A simple method for avoiding the difficulty of weighing an object carrying an electrostatic charge has been proposed by which the correct weight can be obtained.
Zusammenfassung Ein einfaches Verfahren wird beschrieben, mit dessen Hilfe sich die beim Wägen elektrostatisch geladener Objekte ergebenden Schwierigkeiten vermieden und korrekte Gewichtsangaben ermittelt werden können.
Résumé Pour éviter la difficulté de peser un objet portant une charge électrostatique, on a proposé une méthode simple qui permet d'obtenir le poids correct.相似文献
992.
Y. Yoshida T. Nakazawa H. Yoshikawa T. Nakanishi 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(3):541-545
A partition coefficient (λ) for Ra in gypsum was determined from coprecipitation experiment using oversaturation method. The λ-value derived for Ra was: λ
Ra = 0.32±0.15. Saturation state was estimated with the initial concentration of Ca and SO42− in an experiment of the present study. Saturation index was calculated to be (0.49±0.02). This value was similar to those
corresponds to analogous case where slow precipitation rate was kept in coprecipitation experiment for Sr in gypsum. Therefore,
derived λ-value is thought to describe partition of Ra and Ca in solid phase and solution under an equilibrium condition without the
effect of kinetic of precipitation. Determined λ-value was compared with those of other alkaline elements in sulfate minerals. The derived λ-value is smaller than that of Ra in barite and is similar to those of Sr in gypsum. This trend agrees with mechanical understanding
for the size effect against partition coefficient. 相似文献
993.
994.
Takeshi Hasegawa Hiroaki Kubo Koichi Shinozaki Masahiko Nowatari Masahiro Ishii 《Biomedical chromatography : BMC》2010,24(6):613-619
A simple, sensitive and specific chemiluminescent high‐performance liquid chromatography method, based on the luminol reaction, for determination of serum cortisol and cortisone, was established. In infants, placental 11β‐hydroxysteroid dehydrogenase type 2 enzyme (11β‐HSD2) activity may affect adrenal function early after birth. The cortisol–cortisone ratio of serum concentrations in umbilical cord blood is an indicator of placental 11β‐HSD2 activity. The optimum conditions for the luminol reaction were determined to be 1.5 mM luminol, 0.6 M sodium hydroxide, 0.15 mm potassium hexacyanoferrate(III) and 200 mM potassium hexacyanoferrate (II). The calibration curves for cortisol and cortisone exhibited good linearity. The correlation coefficients of the calibration curves were 0.996. The intra‐ and inter‐day precisions were in the ranges: cortisol 7.0–12.2 and 4.4–9.2%, cortisone 5.3–7.0 and 6.2–9.9%. The recoveries of these steroids were in the ranges: cortisol 97–105%, cortisone 94–102%. The limits of detection were as follows: cortisol, 0.17 μg/dl; cortisone 0.15 μg/dl. This assay could be successfully applied to determination of the cortisol–cortiosone ratio of serum concentrations in umbilical cord bloods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
995.
Hiroaki Oie Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5357-5363
Thermally induced ring‐opening polymerization of monofunctional N‐allyl‐1,3‐benzoxazine 1a was compared with that of N‐(n‐propyl)‐1,3‐benzoxazine 1b to clarify an unexpected effect of allyl group to promote the polymerization, that is, in spite of the comparable bulkiness of allyl group to n‐propyl group, the polymerization of 1a was much faster than that of 1b . Such a difference in polymerization rate was also observed similarly in the comparison of thermally induced polymerization of a bifunctional N‐allyl‐benzoxazine 2a with that of a bifunctional N‐(n‐propyl) analogue 2b . These observations implied a certain contribution of an electron‐rich C? C double bond of the N‐ally group to promotion of the ring‐opening reaction of 1,3‐benzoxazine into the corresponding zwitterionic species, which would involve a mechanism to stabilize the cationic part of the zwitterionic species based on “neighboring group participation” of the C? C double bond. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
996.
997.
M Yoshikawa T Morikawa K Yashiro T Murakami H Matsuda 《Chemical & pharmaceutical bulletin》2001,49(11):1452-1456
New dammarane-type triterpene saponins, notoginsenosides-L, -M, and -N, were isolated from the glycosidic fraction of the dried roots of Panax notoginseng (Burk.) F. H. Chen. Their structures were elucidated on the basis of chemical and physicochemical evidence. Immunological adjuvant activities of the principal notoginsenosides and related dammarane-type triterpene saponins were examined and notoginsenosides-D, -G, -H, and -K were found to increase the serum IgG level in mice sensitized with ovalbumin. 相似文献
998.
Bungo Ochiai Tomomi Nagasawa Yasuhiro Asano Daisuke Nagai Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2007,45(13):2820-2826
Thermal behaviors were monitored by infrared thermographic analysis in the copolymerization of a spiroorthoester and a bifunctional oxetane with thermally latent initiators [benzyl tetrahydrothiophenium hexafluoroantimonate (BTHT) and benzyl 4‐hydroxyphenyl methyl sulfonium hexafluoroantimonate (BPMS)]. The copolymerization with BPMS increased the temperature during the copolymerization more than that with BTHT, whereas the exothermicities were lowered with the increase in the initial feed ratio of the spiroorthocarbonate monomer. The high exothermicity in the copolymerization with BPMS is ascribable to the faster propagation of the oxetane monomer with a high heat of polymerization, and this is supported by model reactions and computational calculation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2820–2826, 2007 相似文献
999.
Takeshi Furuta Shuichi Ikefuji Koujirou Tokunaga Tze Loon Neoh Hidefumi Yoshii 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):21-27
Recently, air and ground water pollution and contamination of soil by toluene have been drawing increasing attention and became
an urgently important problem in environmental pollution. Hence, the development of highly sophisticated removal techniques
of toluene is required for the global environmental preservation. Since toluene is a highly volatile material, it is difficult
to treat it by usual activated sludge water treatment. In this study, in order to prevent volatilization of toluene, randomly
methylated β-cyclodextrin (RM-β-CD) was used to complex with toluene and by reason of that, facilitates the biodegradation
of toluene by activated sludge. The enhanced effect of RM-β-CD for the biodegradation of toluene by activated sludge was studied
in batch systems. The addition of RM-β-CD dominantly promoted proliferation of activated sludge. This implied that the addition
of RM-β-CD prevented toluene from evaporating during treatment, and as a result, toluene was effectively decomposed by the
activated sludge. 相似文献
1000.
Two-dimensional quantum fields in electric and gravitational backgrounds can be described by conformal field theories, and hence all the physical (covariant) quantities can be written in terms of the corresponding holomorphic quantities. In this paper, we first derive relations between covariant and holomorphic forms of higher-spin currents in these backgrounds, and then, by using these relations, obtain higher-spin generalizations of the trace and gauge (or gravitational) anomalies up to spin 4. These results are applied to derive higher-moments of Hawking fluxes in black holes in a separate paper [S. Iso, T. Morita, H. Umetsu, Hawking radiation via higher-spin gauge anomalies, arXiv: 0710.0456 [hep-th]]. 相似文献