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71.
Joonho Lee Wataru Shimoda Toshihiro Tanaka 《Monatshefte für Chemie / Chemical Monthly》2005,40(10):1829-1834
Temperature dependence of the surface tension of liquid Sn–Ag and Sn–Cu base lead-free solder alloys and oxygen partial pressure
dependence of liquid Sn–Ag alloy were evaluated using the experimental data obtained, respectively, by the constrained drop
method and the sessile drop method in the previous studies [1, 2]. The temperature dependences of the surface tension have
maximum positive values when the mol fraction of Ag and Cu is about 0.7, while those for pure liquid Sn, Ag, and Cu have negative
values. The calculated values based on Butler’s equations were found to be in reasonable agreement with those of the experimental data. The oxygen partial pressure dependences
of the surface tension of liquid Sn–Ag alloys at 1253 K have a minimum value when the mol fraction of Ag is about 0.9 and
the oxygen partial pressure is less than about 10−13 atm. From this, it is considered that the oxygen adsorption increased by adding Ag to Sn when the mol fraction of Ag is less
than 0.9. 相似文献
72.
Yoshio Tanaka Morishige Atsukawa Yukio Shimura Akira Okada Hideki Sakuraba Tokuji Sakata 《Journal of polymer science. Part A, Polymer chemistry》1975,13(5):1017-1028
A soluble and self-crosslinkable linear copolymer with pendant epoxy and pyridyl groups was obtained from glycidyl methacrylate (M1) and 2-vinylpyridine (M2) or 2-vinyl-5-ethylpyridine (M2) by the action of azobisisobutyronitrile. The monomer reactivity ratios were determined in tetrahydrofuran at 60°C: r1 = 0.510, r2 = 0.620 with 2-vinylpyridine and r1 = 0.57, r2 = 0.62 with 2-vinyl-5-ethylpyridine. These were consistent with the calculated values with the reported Q and e values for these monomers. The intrinsic viscosities of the copolymers with 2-vinylpyridine and with 2-vinyl-5-ethylpyridine were found to be 0.17–0.19 and 0.26–0.38, respectively, in tetrahydrofuran at 30°C; they were independent of the copolymer composition. The copolymers were amorphous, had no clear melting points, and became insoluble crosslinked polymers under heating without further addition of any curing agents. 相似文献
73.
The properties of some chelate-forming resins prepared from common anion-exchange resins by treatment with reagents bearing chelate-forming and ion-exchange groups have been studied. A resin prepared from the sulphonic acid derivative of dithizone (DzS) was found to be superior to other chelate-forming resins. Resins loaded with DzS, tetraphenylporphinetrisulphonic acid or zincon were stable in 1M sodium chloride. Resins prepared from sulphonazo III, arsenazo III, thiosalicylic acid or p-mercaptobenzenesulphonic acid were found to be unstable when exposed to sodium chloride solution. 相似文献
74.
An improved gas chromatographic method, involving the use of a wide-bore capillary column, for the determination of trimethadione and its only demethylated metabolite, dimethadione, in human serum is described. The results indicate that both substances and the internal standard (maleinimide) were well separated with no tailing peak. The detection limit was 10 ng/ml for trimethadione and 50 ng/ml for dimethadione. This improved method is reliable in terms of sensitivity, selectivity and reproducibility for the simultaneous determination of both compounds in human serum. 相似文献
75.
Effects of metal elements on beta-hexosaminidase release from rat basophilic leukemia cells (RBL-2H3). 总被引:1,自引:0,他引:1
Immediate allergy is caused by a chemical mediator released from basophile and mast cells via cell degranulation due to reaction between an immunoglobulin E (IgE) antibody, bound with the IgE receptor on the cell membrane, and an antigen. The present authors have established a new method for assaying the enzyme activity of beta-hexosaminidase as an index of chemical mediator release. Using cultured cells instead of conventional methods based on histamine release from mast cells, the present method permits highly accurate mass screening since it uses a well-established cell line of rat basophilic leukemia cells (RBL-2H3). The effects of metal elements on immediate allergic reaction were evaluated using a newly developed assay system. A total of 38 metal elements were investigated for effects on immediate allergic reactions in vitro. These elements were classified by five types on the basis of action on beta-hexosanimidase release: 1) those which showed very strong inhibitory action, such as ZnCl2 and ZrCl4, 2) those which showed relatively strong inhibitory action, such as CdCl2 and CuCl2, 3) those which showed relatively weak inhibitory action, such as CoCl2 and Pb(NO3)2, 4) those which showed neither inhibitory nor promoting action, such as MnCl2 and SrCl2, and 5) AgNO3, which alone showed promoting action. 相似文献
76.
Kunitaka Muramatsu Masaji Shimazu Junzo Tanaka Shigeo Horiuchi 《Journal of solid state chemistry》1981,36(2):179-182
Complex bismuth oxides with layered structure are prepared with a series of compositions in the system Bi2CaNb2O9-NaNbO3. It is found by X-ray powder diffraction that each compound is composed of more than two phases, which are described by a formula Bi2CaNan?2NbnO3n+3, e.g., in the sample with the nominal composition Bi2CaNb2O9 · 8NaNbO3, the phases with n = 6 to 8 appear predominantly. These phases are closely intergrown to each other. Moreover, high-resolution electron microscopy reveals that microsyntactic intergrowth frequently occurs in the phases with n > 5. The occurrence of the latter intergrowth is explained in terms of the bond length obtained. 相似文献
77.
H. Tanaka 《Journal of Thermal Analysis and Calorimetry》1984,29(5):1115-1122
The thermal dehydration kinetics of crystalline powders of (COOH)2 · 2 H2O was examined by thermogravimetry both at constant and linearly increasing temperatures. An Avrami-Erofeyev law is found to hold with a possibility that a phase-boundary controlled reaction proceeds simultaneously. This is supported by the particle size effect on the rate constant. The activation energyE for the dehydration is estimated as around 80 kJ mol–1. It is likely that the effects of particle size and temperature onE are compensated by those on the frequency factorA.
This work was partly supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture. The author wishes to thank Mr. K. Kawabata for his assistance in the experimental part of this work. 相似文献
Zusammenfassung Die Kinetik der thermischen Dehydratisierung von kristallinen Pulvern von (COOH)2 · 2 H2O wurde thermogravimetrisch bei konstanter und linear ansteigender Temperatur untersucht. Es wurde festgestellt, da\ das Avrami-Erofeyev-Gesetz gefolgt wird und die Möglichkeit besteht, da\ gleichzeitig eine phasen grenzflÄchen-kontrollierte Reaktion verlÄuft. Dies wird durch die Beeinflussung der Geschwindigkeitskonstante durch die Partikelgrö\e unterstützt. Die AktivierungsenergieE für die Dehydratisierung wurde zu etwa 80 kJ mol–1 gefunden. Es ist wahrscheinlich, da\ die Effekte von Partikelgrö\e und Temperatur aufE durch den des HÄufigkeitsfaktorsA kompensiert werden.
, . , — , - . . E 80 · –1. , E A.
This work was partly supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture. The author wishes to thank Mr. K. Kawabata for his assistance in the experimental part of this work. 相似文献
78.
The ionic conductivity was measured in the temperature range 250–300 K as a function of composition of superionic conducting glasses in the pseudobinary system AgIAg2MoO4. The conductivity, ranging from 10?2 to 10?4 Ω?1 cm?1 at room temperature, increases linearly in logarithmic scale with increasing AgI content, while the total silver ion concentration remains nearly constant in the whole glass-forming region of the present system. Such a composition dependence of conductivity is considered to be evidence that only a fraction of the silver ions in glass contributes to the ionic conduction. The conductivity and the activation energy for conduction differ slightly between bulk glasses and pressed pellets of pulverized glasses. The close agreement in bulk glasses and pellets suggests that bulk rather than grain boundary or surface diffusion dominates the conduction process in the present glasses. 相似文献
79.
The ν2 (CD3 symmetrical deformation) and ν5 (CD3 degenerate deformation) fundamental bands of CD3Br were studied by 9.4- and 10.4-μm CO2 laser Stark spectroscopy. Stark resonances originating from 28 and 53 rovibrational transitions of the ν2 and ν5 bands, respectively, were assigned for each of the isotopic species, CD379Br and CD381Br. These two bands were simultaneously analyzed with explicit inclusion of the ν2-ν5 Coriolis interaction, yielding precise molecular constants in the ν2 and ν5 excited states as well as the Coriolis coupling constant. The molecular constants obtained are consistent between the two isotopic species and are in good agreement with the results of high-resolution infrared studies. The band origins and dipole moments are
CD379Br | CD381Br | |||||
991.396 82 (18) | 991.388 46 (17) | cm?1 | ||||
1055.469 00 (12) | 1055.466 32 (12) | cm?1 | ||||
1.830 42 (52) | 1.829 84 (47) | D | ||||
1.829 93 (48) | 1.829 57 (46) | D | ||||
1.832 23 (60) | 1.831 19 (56) | D |