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81.
The size distribution of new vesicles formed after addition of oleate in different forms to preformed egg yolk phosphatidylcholine (EggPC) vesicles was studied by gel exclusion chromatography. The addition of oleate to preformed vesicles resulted in the formation of new small vesicles. Fission of preformed vesicles incorporated by oleate and partial solubilization of the vesicles by addition of oleate in micellar form were involved in the process of the new small vesicle formation. 相似文献
82.
Mochida T Takazawa K Matsui H Takahashi M Takeda M Sato M Nishio Y Kajita K Mori H 《Inorganic chemistry》2005,44(23):8628-8641
Charge-transfer salts of branched-alkyl biferrocenes, (1',1' '-R2-1,1' '-biferrocene)[Ni(mnt)2] (1a, R = isopropyl; 2a, R = dineopentyl) and (1',1' '-R2-1,1' '-biferrocene)2[Co(mnt)2]2 (1b, R = isopropyl; 2b, R = dineopentyl), were prepared. Their valence states were investigated using X-ray crystallography and M?ssbauer spectroscopy. Complexes 1a and 1b show segregated-stack crystal structures that contain columns of acceptors, whereas structures of 2a and 2b, which contain bulky donors, are rather discrete. All of the complexes contain mixed-valent biferrocenium monocations. A two-step valence transition was found in complex 1a. The crystal contains two crystallographically independent cations: one undergoes valence localization below room temperature; the other undergoes valence localization below ca. 130 K. The former transition is derived from asymmetry of the crystal environment around the cation, whereas the latter one is caused by symmetry lowering coupled with a spin-Peierls transition (T(C) = 133.2 K) associated with the dimerization of the acceptors. This compound was found to exhibit a dielectric response based on valence tautomerization. Other complexes (1b, 2a, and 2b) show a valence-trapped state. In all complexes, charge localization was found to occur through local electrostatic interactions between the donor's cationic moiety and the acceptor's electronegative moieties. 相似文献
83.
84.
Conclusion In both cases, brittle fracture and dropping breakdown, only very little deformation or elongation was observed in the experiments mentioned above, and limiting conditions were obtained reproducibly with respect to rate of extension and temperature. The brittle limits give the condition where the viscous resistance due to locally concentrated stress, i. e. the grip effect (5) exceeds cohesion of the materials, and development of the surface of separation is followed. At the dropping limits, the viscosities of the liquids may be too small to resist shrinking by surface tension with respect to the rate of extension. Although the theory of spinnability proposed here may be only tentative, it can be pointed out that surface tension plays some important role in spinning of viscous liquids of lower molecules. Concerning higher molecules, rubber-like elasticity as well as viscosity may become more important (6).
Zusammenfassung Für beide Fälle, spröden Bruch und stufenweiser Bruch, wurde nur sehr geringe Deformation oder Verlängerung beobachtet und Grenzbedingungen hinsichtlich Dehnungsgeschwindigkeit und Temperatur reproduzierbar erhalten. Die Bruchgrenzen geben die Bedingungen, bei denen der viskose Widerstand entsprechend den lokalen Spannungskonzentrationen, d. h. entsprechend den grip-Effekt die Kohäsion des Materials übersteigt, und die Entwickelung der Trennfläche wird verfolgt. Bei der Grenzbelastung für das Absinken der Spannung mag die Viskosität der Flüssigkeiten zu gering sein, um dem Schrumpfen durch Oberflächenspannung im Vergleich mit der Dehnungsgeschwindigkeit entgegen zu wirken. Obgleich die Theorie der Spinnbarkeit, hier vorgeschlagen, nur einen Versuch darstellt, kann behauptet werden, daß die Oberflächenspannung beim Spinnen viskoser Flüssigkeiten mit kleineren Molekülen eine wichtige Rolle spielt. Für höhermolekulare Substanzen wird neben der Viskosität auch die Gummielastizität ausschlaggebend.相似文献
85.
Masami Hasegawa Masaharu Tanemura 《Annals of the Institute of Statistical Mathematics》1976,28(1):509-519
Summary In this paper the tesselation of territories is discussed. When a mass of animals with teritoriality is introduced at random
simultaneously into a finite two-dimensional (2D) region, territories are gradually formed and finally settle to a steady
state. A model calculation for this process is carried out, where a Voronoi polygon is assumed as a territory. Comparisons
are made between the model calculation and Barlow's observation on an artificial population of mouthbreeder fish. Differences
between 1D and 2D case are also discussed.
The Institute of Statistical Mathematics 相似文献
86.
87.
F. P. He?berger S. Antalic B. Sulignano D. Ackermann S. Heinz S. Hofmann B. Kindler J. Khuyagbaatar I. Kojouharov P. Kuusiniemi M. Leino B. Lommel R. Mann K. Nishio A. G. Popeko ?. ?áro B. Streicher J. Uusitalo M. Venhart A. V. Yeremin 《The European Physical Journal A - Hadrons and Nuclei》2010,43(1):55-66
A detailed $ \gamma$ spectroscopic decay study of two K isomers in 254No was performed. In addition to the previously reported $ \gamma$ lines two new transitions of E = 778 , 856keV could be attributed to the decay pattern of 254m1No ( T 1/2 = 275±7 ms). The population of an excited band built up on this isomer ( $\ensuremath K^{\pi} =8^{-}$ by the decay of 254m2No ( T 1/2 = 198±13 μs) could be proven by measuring delayed $ \gamma$ - $ \gamma$ coincidences between transitions stemming from the decay of both isomeric states. The energies of the band members could be established up to $\ensuremath I^{\pi} = 15^{-}$ . A spontaneous fission branch of (2.0±1.2)×10-4 was measured for 254m1No , an upper limit of $ \le$ 1.2×10-4 was estimated for 254m2No . These values demonstrate the high stability of multi-quasiparticle configurations against spontaneous fission. Evidence for an $ \alpha$ decay branch of 254m1No in the order of 1×10-4 was found. 相似文献
88.
Scanning-tunneling spectroscopy at 5 K was used to investigate the electrostatic potential profile on the Si(111)-square root of 3 x square root of 3 Ag surface at subnanometer spatial resolution. The potential was measured from an energy-level shift of electronic states on the surface. The potential images obtained reveal that the potential drops around the steps and Ag adsorbates, upon which positive charges are presumably accumulated. The profiles of the reduced potentials are explained with the screening of potential due to the charges by two-dimensional electron gas (2DEG) existing on the surface. The Friedel oscillation, which results from the screening and has a period of the half Fermi wavelength of the 2DEG, was also observed in the potential images. 相似文献
89.
Higashi T Takayama N Nishio T Taniguchi E Shimada K 《Analytical and bioanalytical chemistry》2006,386(3):658-665
A practical procedure for determining estrogens in biological fluids has been studied using liquid chromatography–electron
capture atmospheric pressure chemical ionization–mass spectrometry combined with derivatization. Among the commercially available
reagents (4-nitrobenzoyl chloride, 2,4-dinitrofluorobenzene, 4-nitrobenzenesulfonyl chloride and 4-nitrobenzyl bromide), 4-nitrobenzenesulfonyl
chloride was of the most practical use; it rapidly and quantitatively reacted with estrogens and increased the detection responses
by 8–23 times. The derivatization method allowed the reproducible and accurate quantification of serum and urine estrone and
estradiol of a pregnant woman, which is useful for diagnosis of the fetoplacental function, with small amounts (10 μl) of
sample and a simple pretreatment procedure.
Tatsuya
Higashiis Associate Professor of the Laboratory of Clinical Analytical Sciences (Professor Kazutake Shimada’s research group) at
the Graduate School of Natural Science and Technology of Kanazawa University. He received the Japan Society for Analytical
Chemistry Award for Young Scientists in 2003 and the Pharmaceutical Society of Japan Award for Young Scientists in 2006. His
current research interests are the development of methods for increasing sensitivity in LC-MS to detect and characterize trace
amounts of biologically active steroids, such as estrogens, androgens and neuroactive steroids. 相似文献
90.