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71.
Koga K Takekoshi K Kawashima S Taniguchi M Murakami M 《Chemical & pharmaceutical bulletin》2004,52(12):1507-1510
One persistent problem with using therapeutic concentrations of glycyrrhizin (GZ) is that, at these high concentrations, it forms a gel in an aqueous solution. We previously solved this problem by dissolving GZ in a highly concentrated phosphate buffer. Unfortunately, the resulting GZ solution has a hyperosmotic pressure that renders it unsuitable for use in patients. The aim of this study was to prepare a highly concentrated GZ solution having an osmotic pressure ratio of 1 and a pH of 7.4. By adding small amounts of oil and using a 100 mM phosphate buffer, we achieved an emulsified GZ solution that is stable at room temperature and has a physiological osmotic pressure and pH. When clove oil was used as an emulsifier, the gel formation temperature of GZ solution decreased appreciably compared to that of GZ solution without clove oil. Using scanning electron microscopy (SEM), we examined the detailed characteristics of GZ gels prepared from solutions with or without clove oil. SEM of cross sections of GZ gels revealed an irregular structure in gels prepared with clove oil, indicating that clove oil prevented the formation of the intermolecular GZ networks typically characterized by gels derived from pure GZ solutions. 相似文献
72.
Koga T 《The Journal of chemical physics》2004,121(8):3939-3940
In many-electron atoms, the average electron radius r represents the mean distance of a single electron from the nucleus when all the interelectronic interactions are averaged. If the electron-electron interaction is explicitly considered, the average radius r splits into two different radii, inner radius r(<) and outer radius r(>). For the 102 atoms He through Lr in their ground states, the radii r(<) and r(>) are systematically examined at the Hartree-Fock limit level. The effect of electron correlations on r(<) and r(>) is also discussed for the He atom and its isoelectronic ions. 相似文献
73.
Higashiguchi T. Hirata T. Koga M. Rajyaguru C. Sasaki W. Kubodera S. 《Applied physics. B, Lasers and optics》2004,79(5):587-590
We investigated characteristics of the soft X-ray emission in the wavelength range of 6–16 nm using various rare-gas cryogenic solid targets irradiated with a nanosecond laser pulse. Suprathermal ions having a maximum velocity of the order of 107 cm/s were detected for three rare-gas targets (Ar, Kr, and Xe). The spatial distributions of the soft X-rays and the suprathermal ions were measured for Xe cryogenic solid targets and found to vary as cos2 and cos5, respectively, where is the angle to the target normal. By integrating the observed cos2 spatial distribution, the conversion efficiency of the soft X-ray emission in the wavelength range from 6 to 16 nm was evaluated to be 0.2%/pulse. PACS 52.38.ph; 52.50.Jm 相似文献
74.
In order to investigate the space environment, a new neutron monitor has been prepared. The sensor consists of scintillation fibers (FIB) and will be on board the exposed facility of the Japanese Experimental module (Kibo) of the International Space Station (ISS). The sensor is one of the instruments which measures the particle and plasma environment around the ISS. The sensor will be used by the cosmonauts who work on the ISS, to help them avoid a strong particle radiation which may arrive soon. We believe that such an alert is necessary for the cosmonauts to prevent unnecessary radiation from the sun. Furthermore, the sensor will be very useful in understanding the particle acceleration mechanism at the solar surface. The design of the Engineering Model (EM) was finished and its properties were investigated. This report discusses these results. 相似文献
75.
Yamazaki E. Inuzuka F. Yonenaga K. Takada A. Koga M. 《Photonics Technology Letters, IEEE》2007,19(1):9-11
A scheme that compensates the waveform distortion induced by nonlinear interchannel crosstalk such as four-wave mixing (FWM) and cross-phase modulation as well as self-phase modulation in phase-locked wavelength-division-multiplexing transmission systems is proposed. Reduction of FWM-induced waveform distortion by controlling the phase relationship between neighbouring channels and its cancellation by precompensation is successfully demonstrated 相似文献
76.
77.
All-optical timing extraction using an optical tank circuit 总被引:3,自引:0,他引:3
An ultrafast all-optical timing extraction method using an optical tank circuit is described, and experimental results at 2 Gb/s are reported. A Fabry-Perot resonator, whose free spectral range is equal to the clock frequency of the incoming optical data stream, is utilized as the optical tank circuit. Its fully passive structure and ultra-high-bit-rate operation (~Tb/s) is possible through decreasing resonator length 相似文献
78.
This paper presents measured and calculated data that can be used as a basis for designing and protecting telecommunication equipment against lightning-induced surges in Japan. The paper examines the variations in geographic and environmental conditions in different parts of Japan (e.g., thunderstorm days, summer versus winter lightning, ground (soil) conductivity) and describes measured variations in lightning-induced surge characteristics in subscriber-paired cables due to differences in geographic conditions and cable conditions (e.g., cable type, buried versus aerial cable, cable length, cable height, terminal conditions, main versus branch cable). Measured lightning characteristics (e.g., front time, time-to-half-value) are compared for various measurement locations (e.g., subscriber end for subscriber cable, telephone office end for subscriber cable, telephone office end for toll cable). A general set of equations is empirically derived that predicts lightning-induced surgevoltage occurrences, front time, and time-to-half-value distributions. 相似文献
79.
80.
Welter R. Sessa W.B. Maeda M.W. Wagner R.E. Curtis L. Young J. Lee T.P. Nanduri K. Kodera H. Koga Y. Barry J.R. 《Lightwave Technology, Journal of》1989,7(10):1438-1444
An experimental 155.52 Mb/s coherent broadcast network with 16 channels using a conventional distributed feedback (DFB) laser operating at 1540 nm is described. It includes absolute laser frequency stabilization, a fiber span of 74.4 km, and a balanced polarization-diversity single-filter frequency-shift keying (FSK) heterodyne receiver. At a channel spacing of 8.5 GHz a power penalty of 0.3 dB is incurred due to adjacent channel crosstalk 相似文献