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31.
Papadimitriou V Barker A Briere RA Gibbons LK Makoff G Patterson JR Somalwar S Wah YW Winstein B Winston R Woods M Yamamoto H Swallow EC Bock GJ Coleman R Enagonio J Hsiung YB Ramberg E Stanfield K Tschirhart R Yamanaka T Gollin GD Karlsson M Okamitsu JK Debu P Peyaud B Turlay R Vallage B 《Physical review D: Particles and fields》1991,44(3):R573-R576
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Interfacial tension () between aqueous dodecyltrimethylammonium chloride (DTAC) solution and benzene was measured as a function of pressure (p) and concentration. The/p was observed to change discontinuously at the critical micelle concentration; this indicates that the micelle formation of DTAC in the aqueous solution coexisting with benzene can be treated like the appearance of a macroscopic phase. It was shown by drawing the vs.A curves that hydrocarbon, such as benzene, cyclohexane, and hexane, make the adsorbed film of DTAC expand. The volume behavior of the micelle with benzene molecules solubilized was found to bear a strong resemblance to that of the adsorbed film at the water/benzene interface. The difference in the molar volume value of adsorbed DTAC among the coexistent hydrocarbon phases was attributed to the difference in the contribution of the hydrocarbon molecules to the interfacial excess volume; the number of the solubilized hydrocarbon molecules was evaluated to be one or two a micelle. 相似文献
34.
Microchip-based immunoassay system with branching multichannels for simultaneous determination of interferon-gamma 总被引:1,自引:0,他引:1
A bead-bed immunoassay system suitable for simultaneous assay of multiple samples was constructed on a microchip. The chip had branching multichannels and four reaction and detection regions; the constructed system could process four samples at a time with only one pump unit. Interferon gamma was assayed by a 3-step sandwich immunoassay with the system coupled to a thermal lens microscope as a detector. The biases of the signal intensities obtained from each channel were within 10%, and coefficients of variation were almost the same level as the single straight channel assay. The assay time for four samples was 50 min instead of 35 min for one sample in the single-channel assay; hence higher throughput was realized with the branching structure chip. 相似文献
35.
Enami S Yamanaka T Hashimoto S Kawasaki M Tonokura K 《The journal of physical chemistry. A》2005,109(27):6066-6070
The reactions of Cl atoms with RI (R = n-C3H7, n-C4H9, cyclo-C6H11, C6H5, C6F5, and p-CH3C6H4) have been studied using cavity ring-down spectroscopy at a temperature range of 233-313 K and at 100 Torr total pressure of N2 diluent. Visible absorption spectra of the RI-Cl adducts were recorded at 440-520 nm at 263 K. The yields of the adducts were temperature-dependent. There was no discernible reaction of the adducts in the presence of 100 Torr of O2 at 263 K. Theoretical calculations were performed for C4H9I-Cl and C6H5I-Cl for quantitative explanation of the absorption spectra and the strength of the I-Cl bonds in the charge-transfer complexes. Evidence for the adduct formation following the reaction of Cl with C6H5Br was sought but not found at 440 and 520 nm. 相似文献
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Komeda S Lutz M Spek AL Yamanaka Y Sato T Chikuma M Reedijk J 《Journal of the American Chemical Society》2002,124(17):4738-4746
The reactions of the dinuclear platinum(II) complexes, [[cis-Pt(NH(3))(2)](2)(mu-OH)(mu-pz)](NO(3))(2) (1, pz = pyrazolate), [[cis-Pt(NH(3))(2)](2)(mu-OH)(mu-1,2,3-ta-N1,N2)](NO(3))(2) (2, 1,2,3-ta = 1,2,3-triazolate), and a newly prepared [[cis-Pt(NH(3))(2)](2)(mu-OH)(mu-4-phe-1,2,3-ta-N1,N2)](NO(3))(2) (3, 4-phe-1,2,3-ta = 4-phenyl-1,2,3-triazolate), whose crystal structure was determined, with 9-ethylguanine (9EtG) have been monitored in aqueous solution at 310 K by means of (1)H NMR spectroscopy. The dinuclear platinum(II) complexes 1-3 each react with 9EtG in a bifunctional way to form 1:2 complexes, [[cis-Pt(NH(3))(2)(9EtG-N7)](2)(mu-pz)](3+) (4), [[cis-Pt(NH(3))(2)(9EtG-N7)](2)(mu-1,2,3-ta-N1,N3)](3+) (5), and [[cis-Pt(NH(3))(2)(9EtG-N7)](2)(mu-4-phe-1,2,3-ta-N1,N3)](3+) (6). The reactions of 2 and 3 involve a novel isomerization, in which the Pt atom, initially bound to N2 on the 1,2,3-ta, migrates to N3 after the first substitution by N7 of 9EtG. This isomerization reaction has been unambiguously characterized by 1D and 2D NMR spectroscopy and pH titration. The reactions of 2 and 3 with 9EtG show faster kinetics, and the second-order rate constants (k) for the reactions of 1-3are 1.57 x 10(-4), 2.53 x 10(-4), and 2.56 x 10(-4) M(-1) s(-1), respectively. The pK(a) values at the N1H site of 9EtG were determined for 4-6 from the pH titration curves. Cytotoxicity assays of 1-3 were performed in L1210 murine leukemia cell lines, respectively sensitive and resistant to cisplatin. In the parent cell line, 2 and 3 exhibit higher cytotoxicity compared to cisplatin, especially, 2 is 10 times as active as cisplatin. 1 was found to be less cytotoxic than cisplatin, but still in the active range and more active than cisplatin in a cisplatin-resistant cell line. 相似文献
37.
S. Iwama N. Satomi M. Yamanaka S. Goto T. Ishimura H. Ito 《International Journal of Infrared and Millimeter Waves》1981,2(6):1199-1208
A high-power CW 27.972 m water vapor laser has been constructed in order to use as a light source of an interferometer for plasma diagnostics. The laser consists of 220 cm length and 2.0 cm small bore Pyrex glass discharge tube, semi-confocal resonator and Michelson coupler. From the measurement of cavity detuning curves, it is found that two waveguide modes, EH11 and EH21 oscillate. The increase of the output power is found to become more than seven times larger by adding He(50%)–H2(50%) mixed gas. Under the optimum condition, the maximum output power of 65 mW or the output power per unit cavity volume of 83 W/cm3 is obtained. 相似文献
38.
The densities and elastic properties of RO · SiO2 and RO · 2 SiO2 glasses (R = Mg, Ca, Sr, Ba or their mixtures) have been determined to obtain the compositional dependences of volume and bulk modulus of alkaline-earth silicate glasses. The mean atomic volume was found to vary almost linearly with glass composition for a series of RO · SiO2 or RO · 2SiO2 glasses, although there exists a slight negative deviation from the linearity for RO · 2SiO2 glasses when two kinds of alkaline-earth oxides were mixed. The change in glass volume agreed fairly well with the value calculated on the basis of the difference in ionic size of alkali-earth ions being subtituted each other. The bulk moduli of RO · SiO2 and RO · 2SiO2 glasses were found to vary in reciprocal proportion to the four-thirds power of the volume when R was changed from one kind to another, indicating that the difference in internal energy of glass arises mainly from the change in Coulombic attraction due to their size difference. These results seemed to show that the glass structure of a series of RO · 2SiO2 or RO · 2SiO2 glasses remains almost unchanged except the local a change around R ions when R is subtituted from one kind to another. 相似文献
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