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51.
Y Yoshida H Takashima Y Kawasaki S Yasuda T Tamai N Hosokawa T Miyamoto S Matuno K Sakamoto S Nakase 《Radioisotopes》1988,37(9):525-528
The clinical significance of serum SCC antigen level was evaluated by the monoclonal antibody method (SCC.RIABEAD Dinabot Co. Ltd). Patients with squamous cell carcinoma showed a high positive SCC antigen level and positive rate elevated with the advance of the clinical stage. The serum SCC antigen level was decreased by treatment, and it increased again before obvious clinical recurrence was recognized. The results suggest that measurement of serum SCC antigen level is useful as a follow up of cancer treatment. 相似文献
52.
S. L. Liu M. L. Chng T. S. Chung K. Goto S. Tamai K. P. Pramoda Y. J. Tong 《Journal of Polymer Science.Polymer Physics》2004,42(14):2769-2779
A series of indan‐containing polyimides were synthesized, and their gas‐permeation behavior was characterized. The four polyimides used in this study were synthesized from an indan‐containing diamine [5,7‐diamino‐1,1,4,6‐tetramethylindan (DAI)] with four dianhydrides [3,3′4,4′‐benzophenone tetracarboxylic dianhydride (BTDA), 3,3′4,4′‐oxydiphthalic dianhydride (ODPA), (3,3′4,4′‐biphenyl tetracarboxylic dianhydride (BPDA), and 2,2′‐bis(3,4′‐dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)]. The gas‐permeability coefficients of these four polyimides changed in the following order: DAI–BTDA < DAI–ODPA < DAI–BPDA < DAI–6FDA. This was consistent with the increasing order of the fraction of free volume (FFV). Moreover, the gas‐permeability coefficients were almost doubled from DAI–ODPA to DAI–BPDA and from DAI–BPDA to DAI–6FDA, although the FFV differences between the two polyimides were very small. The gas permeability and diffusivity of these indan‐containing polyimides increased with temperature, whereas the permselectivity and diffusion selectivity decreased. The activation energies for the permeation and diffusion of O2, N2, CH4, and CO2 were estimated. In comparison with the gas‐permeation behavior of other indan‐containing polymers, for these polyimides, very good gas‐permeation performance was found, that is, high gas‐permeability coefficients and reasonably high permselectivity. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2769–2779, 2004 相似文献
53.
54.
Extraction of vanadium(V) with 8-quinolinol into chlorobenzene is discussed. Three dimeric species are shown to be responsible for the extraction: 2VO3- + 4(HOx)o α (V2O3Ox4)o + 2OH-; log Kex,1 = -1.60 ± 0.10 2VO3- + 4(HOx)o + H+ + ClO4- α (V2O3H(Ox)4 · ClO4)o + 2OH-; log Kex,2 = 1.55 ± 0.10 2VO3- + 4(HOx)o + 2H+ + 2ClO4- α (V2O2Ox4 · 2ClO4)o + 2OH-; log Kex,3 = 2.65 ± 0.10 The vanadium(V) complex of 8-quinolinol has also been studied by thermogravimetry and i.r. and visible spectroscopy; an oxo-bridged dimeric structure is postulated. In contrast to 8-quinolinol, 2-methyl-8-quinolinol gives a monomeric vanadium(V) complex under the usual experimental conditions. 相似文献
55.
Motoharu Inagaki Taichi Isogai Kenta Motobayashi Kai-Qiang Lin Bin Ren Katsuyoshi Ikeda 《Chemical science》2020,11(36):9807
In surface-enhanced Raman spectra, vibrational peaks are superimposed on a background continuum, which is known as one major experimental anomaly. This is problematic in assessing vibrational information especially in the low Raman-shift region below 200 cm−1, where the background signals dominate. Herein, we present a rigorous comparison of normal Raman and surface-enhanced Raman spectra for atomically defined surfaces of Au(111) or Au(100) with and without molecular adsorbates. It is clearly shown that the origin of the background continuum is well explained by a local field enhancement of electronic Raman scattering in the conduction band of Au. In the low Raman-shift region, electronic Raman scattering gains additional intensity, probably due to a relaxation in the conservation of momentum rule through momentum transfer from surface roughness. Based on the mechanism for generation of the spectral background, we also present a practical method to extract electronic and vibrational information at the metal/dielectric interface from the measured raw spectra by reducing the thermal factor, the scattering efficiency factor and the Purcell factor over wide ranges in both the Stokes and the anti-Stokes branches. This method enables us not only to analyse concealed vibrational features in the low Raman-shift region but also to estimate more reliable local temperatures from surface-enhanced Raman spectra.Both electronic and vibrational information at the metal/dielectric interface were explicitly extracted from surface-enhanced Raman spectra. 相似文献
56.
Azobenzene-conjugated mononuclear and dinuclear terpyridyl complexes of Co(II), Co(III), and Fe(II) were synthesized, and their photoisomerization behavior was investigated. Co(II) and Co(III) complexes, [tpyCo(tpy-AB)]X(n) and [(Cotpy)(2)(tpy-AB-tpy)]X(n) (tpy-AB = C(15)N(3)H(10)-C(6)H(4)-N=NC(6)H(5), tpy-AB-tpy = C(15)N(3)H(10)-C(6)H(4)-N=NC(6)H(4)-C(15)N(3)H(10), X = PF(6) or BPh(4)), exhibit trans-to-cis photoisomerization by irradiation at 366 nm, and this behavior is dependent on solvents and counterions. For the Co(II) complexes, BPh(4) salts undergo cis-to-trans isomerization in propylene carbonate by both photoirradiation with visible light (435 nm) and heat, indicating that reversible trans-cis isomerization has occurred. [Co(tpy-AB)(2)](BPh(4))(2) shows a two-step trans-to-cis isomerization process. The trans-cis isomerization behavior of Co(III) complexes was observed only in the solvents with a low donor number such as 1,2-dichloroethane. Fe(II) complexes, [tpyFe(tpy-AB)]X(n) (X = PF(6) or BPh(4)), exhibit slight trans-to-cis photoisomerization due to the energy transfer from the azobenzene moiety to Fe(tpy)(2) moieties. 相似文献
57.
58.
Dr. Akira Watanabe Mutsuo Matsumoto Dr. Rempei Gotoh Hisako Tamai 《Colloid and polymer science》1967,221(1):47-52
Summary In order to discuss the structure of the electrical double layer at the oil-water interface, we measured the electrocapillary curves for various inorganic electrolyte aqueous solutions (aq. phase) in contact with the oil phase containing surface active agents (oil phase). When the aqueous phase contained the potassium halide, the depression of the interfacial tension over the cathodic polarization range due to the adsorption of the surface active agent, i. e. cetyl pyridinium chloride or cytyltrimethylammonium chloride, was suppressed strongly. The suppression was larger for the anion of larger crystal radius. This phenomenon indicated that the adsorbed surface active ion was neutralised by the binding of counter-ions. When the oil phase contained sodium dodecylbenzenesulphonate, the interfacial tension was depressed over the anodic polarization region. This depression was again suppressed by the counter-ion binding. The order of this suppression for various divalent cations agreed with that of the binding ability to chondroitin sulphate. Moreover, high valent cations had strong binding ability. These counter-ion binding support the idea of the penetration of polar groups of orientated surface active agents into the aqueous phase at the oil-water interface.
With 7 figures and 1 table 相似文献
Zusammenfassung Um Aussagen über die Struktur der elektrischen Doppelschicht an Öl-Wasser-Grenzflächen zu erhalten, wurden die Elektrokapillaritätskurven von wässerigen Lösungen verschiedener anorganischer Salze in Kontakt mit der Ölphase, die grenzflächenaktive Stoffe enthielt, gemessen.Die durch Cetylpyridiniumchlorid oder cetyltrimethylammoniumchlorid in der Ölphase bewirkte Erniedrigung der Grenzflächenspannung wurde im Bereich der kationischen Polarisation durch Kaliumhalogenide in der wässerigen Phase aufgehoben. Die Wirkung des anorganischen Salzes wurde mit zunehmendem Anionenradius stärker.Die durch Natriumdodecylbenzolsulfonat bewirkte Erniedrigung der Grenzflächenspannung wurde durch die Kaliumhalogenide im Bereich der anodischen Polarisation aufgehoben. Die Wirkung zweiwertiger Kationen lief parallel mit der Bindungsfestigkeit dieser Ionen an Chondroitinsulfat.Diese Ergebnisse weisen darauf hin, daß die adsorbierten grenzflächenaktiven Ionen in ihrer Wirkung durch die Bindung von Gegenionen neutralisiert werden und daß die polaren Gruppen der an der Öl-Wasser-Grenzfläche orientierten grenzflächenaktiven Molekeln in die wässerige Phase eindringen.
With 7 figures and 1 table 相似文献
59.
Temperature-dependent photoluminescence (PL) and time resolved photoluminescence (TRPL) are performed to study the PL characteristics and carrier transfer mechanism in asymmetric coupled InGaN/GaN multiple quantum wells (AS-QWs). Our results reveal that abnormal carrier tunnelling from the wide quantum well (WQW) to the narrow quantum well (NQW) is observed at temperature higher than about lOOK, while a normal carrier tunnelling from the NQW to the WQW is observed at temperature lower than 100 K. The reversible carrier tunnelling between the two Q Ws makes it possible to explore new types of temperature sensitive emission devices. It is shown that PL internal quantum efficiency (IQE) of the NQW is enhanced to about 46% due to the assistant of the abnormal carrier tunnelling. 相似文献
60.
Isoda T Hayashi K Tamai S Kumagai T Nagao Y 《Chemical & pharmaceutical bulletin》2006,54(11):1616-1619
The tandem and stepwise Staudinger/aza-Wittig reactions of several azides were examined in detail. The tandem reaction method (Method I) exhibited superior results in the yield of the corresponding isothiocyanates bearing an electron-withdrawing group than the conventional stepwise method (Method II) which involves the sequential treatment of the azides with triphenylphosphine and then carbondisulfide. The mechanistic consideration for both reaction methods was proposed on the basis of the 1H-NMR analyses. 相似文献