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101.
The permeabilities of He, H2, N2, O2, CO2, CH4, C2H6, C3H8, and n-C4H10 in poly[1-phenyl-2-[p-(trimethylsilyl)phenyl]acetylene] (PTMSDPA) and poly[diphenylacetylene] (PDPA) are presented and compared to those of poly(1-trimethylsilyl-1-propyne) (PTMSP), poly(1-phenyl-1-propyne) (PPP), and polysulfone. Like PTMSP, PTMSDPA, a disubstituted glassy acetylene-based polymer, exhibits higher permeabilities to organic vapors than to permanent gases due to its rigid polyacetylene backbone and bulky side groups, which provide a relatively high fractional free volume (FFV) value of 0.26. Desilylation was performed on PTMSDPA. The resulting material, PDPA, is totally insoluble in common organic solvents, so it has much higher chemical resistance than PTMSDPA. Additionally, due to its insolubility in polymerization solvents, desilylation provides the only known route to high molar mass PDPA. The FFV of the resulting membrane (PDPA) is reduced by approximately 12% relative to that of PTMSDPA. This leads to a decrease in gas permeability values and selectivity of organic vapors relative to nitrogen. For example, the oxygen permeability is reduced from 1200 to 500 Barrers upon desilylation. The pure gas selectivities decrease from 9 to 3 for n-C4H10/N2 and from 26 to 9 for C3H8/N2. 相似文献
102.
Masaki Himejima Kenneth R. Hobson Toshikazu Otsuka David L. Wood Isao Kubo 《Journal of chemical ecology》1992,18(10):1809-1818
The oleoresin of the ponderosa pine,Pinus ponderosa (Pinaceae) exhibited broad antimicrobial activity. In order to identify the active compounds, the oleoresin was steam distilled
to give a distillate and residue. The distillate contained mainly monoterpenes and some sesquiterpenes, while the residue
consisted chiefly of four structurally related diterpene acids. An antimicrobial assay with the pure compounds indicated that
the monoterpenes were active primarily against fungi, but there was also some activity against gram-positive bacteria. The
diterpene acids, in contrast, only exhibited activity against gram-positive bacteria. Although not all of the identified sesquiterpenes
could be tested, longifolene showed activity only against gram-positive bacteria. Therefore, it appears that the oleoresin
ofP. ponderosa functions as a biochemical defense against microbial invasion. 相似文献
103.
Yoshiaki Kobayashi Toshikazu Nakamura Toshihiro Takahashi Kazushi Kanoda B. Hilti J. S. Zambounis 《Journal of Superconductivity and Novel Magnetism》1994,7(3):663-666
We report the results of our attempt to measure the proton nuclear relaxation rate, 1/T 1, in the superconducting state of the title material. The relaxation rate in the superconducting state at a field of 1 T was found much longer than that in the normal state, but it became clear that the dominant contribution came from the normal core region. The nuclear relaxation at zero field was examined by using the field cycling technique. An ln(t) term in the relaxation curve was observed at low temperatures, suggesting the contribution of the creeping motion of vortices. We discuss the possibility to determine the intrinsic temperature dependence of 1/T 1 in the superconducting state. 相似文献
104.
A high damping condition is easily obtained in Mn-(16~24)Cu-(4~6)Ni-2Fe (at. pct) alloys,when cooling rate is controlled after the solid solution treatment at 1173 K. It is observed that the temperature dependent changes of Iogarithmic decrement in 10 h cooled samples are sensitive to the alloy composition. As compared with water quenching treatment, controlled 10 h cooling improves TN temperature of the alloys extensively by producing a Mn-enriched matrix portion in the alloys. Calcuiations suggest that the relative decreases of Cu and Ni content in the matrix portion be dominated by the Ni content in the original alloys, and therefore, the volume fraction of the Cu, Ni-enriched precipitates is estimated to be about 20% and 10% in the 4Ni and 6Ni alloys, respectively. As a result, the TN temperature fOr each alloy, corresponding to the rising temperature of logarithmic decrement, has been related to the Cu, and Ni content in the Mnenriched matrix. The existence of {110} twinning boundaries is confirmed in the microstructure of both 4Ni and 6Ni alloys. However, the relative lattice strains, which the twinning boundaries act to accommodate, are found largely different in the two alloys. It is considered that boundaries with smaller orientation deviation could coordinate the external Stresses easily by cyclic moving, and therefore, the broader damping peak which occurs in the 10 h cooled 6Ni alloy becomes feasible. Electron diffraction results also indicate possible for mation of many sub-crystals in the matrix phase, which are relatively rotated on some invariant planes. Those sub-crystal boundaries might play some attenuation roles in the temperature range between TN and room temperature. 相似文献
105.
Ohsawa J. Hinata S. Aoyagi T. Kadowaki T. Kaneno N. Ikeda K. Susaki W. 《Electronics letters》1985,21(18):779-780
AlGaAs laser arrays with inner stripe configuration have been developed. Transverse mode control was accomplished by introducing nonuniform refractive index and gain distributions, which are built in utilising growth features of liquid-phase epitaxy. The maximum light outputs are 130 mW and 400 mW in CW and pulsed operation, respectively. 相似文献
106.
Thioether Macrocyclic Peptides Selected against TET1 Compact Catalytic Domain Inhibit TET1 Catalytic Activity
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107.
A composite torsional quartz transducer has been developed for the shear ultrasonic measurements of aqueous solutions in the frequency range from 10 to 100 kHz. In order to prevent the electric interaction and low contact angle between the transducer and water, a torsional quartz crystal transducer is attached to a fused quartz rod whose surface is partly gilded by evaporation. The accuracy of +/-60 dyn/cm2 for the rigidity and +/-0.03 cP for the viscosity is attained by use of this transducer. 相似文献
108.
Emission mechanism in phosphorescent and fluorescent OLED utilizing energy transfer from exciplex to emitter
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Tatsuyoshi Takahashi Satoshi Seo Hiromi Nowatari Shunsuke Hosoumi Takahiro Ishisone Takeyoshi Watabe Satomi Mitsumori Nobuharu Ohsawa Shunpei Yamazaki 《Journal of the Society for Information Display》2016,24(6):360-370
This paper discusses the effectiveness of energy transfer from an exciplex to an emitter in both phosphorescent and fluorescent organic light‐emitting diodes. This energy transfer enhances the efficiency, lowers the drive voltage, and extends the lifetime. The increase in the quantum efficiency of a fluorescent organic light‐emitting diode using this mechanism is also analyzed. 相似文献
109.
Toshikazu Yano Noriyuki Miyazaki Toshikuni Isozaki 《Nuclear Engineering and Design》1983,75(1):157-168
The analytical results of blowdown characteristics and thrust forces were compared with the experiments, which were performed as pipe whip and jet discharge tests under the PWR LOCA conditions. The blowdown thrust forces were obtained by Navier-Stokes momentum equation for a single-phase, homogeneous and separated two-phase flow, assuming critical pressure at the exit if a crifical flow condition was satisfied.The following results are obtained:
- 1. (1) The node-junction method is useful for both the analyses of the blowdown thrust force and of the water hammer phenomena.
- 2. (2) The Henry-Fauske model for subcooled critical flow is effective for the analysis of the maximum thrust force under the PWR LOCA conditions. The jet thrust parameter of the analysis and experiment is equal to 1.08.
- 3. (3) The thrust parameter of saturated blowdown has the same one with the value under pressurized condition when the stagnant pressure is chosen as the saturated one.
- 4. (4) The dominant terms of the blowdown thrust force in the momentum equation are the pressure and momentum terms except that the acceleration term has large contribution only just after the break.
References
[1]M. Okazaki et al., Preprint of two phase flow meeting, JSME (1980), pp. 85–88 (in Japanese).[2]F.J. Moody, ASME 69HT31 (1969).[3]F.J. Moody, Fluid reaction and impingiment loads, Nuclear Power Plants (1973), pp. 219–261.[4]B.R. Strong and R.J. Baschiere, Nucl. Engrg. Des. 45 (1978), pp. 419–428. Abstract | PDF (543 K) | View Record in Scopus | Cited By in Scopus (0)[5]RELAP4/MOD5, ANCR-NUREG-1335 (1976).[6]PRTHRUST, Nuclear Service Co..[7]N. Miyazaki et al., Nucl. Engrg. Des. 64 (1981), pp. 389–401. Abstract | PDF (806 K) | View Record in Scopus | Cited By in Scopus (0)[8]W.H. Retting et al., IN-1321 (1970).[9]M. Hsu et al., Nucl. Technology 53 (1981), pp. 58–63.[10]R.E. Henry and H.K. Fauske, Journal of Heat Transfer, Trans. ASME, Ser. C93 (1971), pp. 179–187. Full Text via CrossRef[11]F.J. Moody, Journal of Heat Transfer, Trans. ASME, Ser. C93 87 (1965), pp. 134–142.[12]N. Miyazaki et al., 1981 Fall Meeting Reactor Phys. and Eng., At. Energy Soc. Japan, Paper D58 (1981) (in Japanese).[13]K. Namatame and K. Kobayashi, Journal of Heat Transfer, Trans. ASME, Ser. C 98 (1976), pp. 12–18. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (0)[14]M. Sobajima, Nucl. Sci. Engrg. 60 (1976), pp. 10–18. View Record in Scopus | Cited By in Scopus (0)[15]R.D. Jain and G.A. Hastings, Trans. Ame. Nucl. Soc. 21 (1975), pp. 345–346. 相似文献110.
A new type of thermosetting resin can be obtained from solventless varnishes composed of polyfunctional isocyanates and epoxides. The IR spectra show that the cured resins have isocyanurate and oxazolidone rings in their chemical structure, hence their name, isocyanurate–oxazolidone resins. The viscoelastic behavior of the cured resins can be varied considerably by selecting an appropriate reactant species and changing the equivalent ratio of the isocyanate and epoxy groups in the varnishes. Three relaxations, labeled α, β, and γ, characterize their dynamic mechanical spectra. The α-dispersion is due to the glass transition, the β-dispersion, to local mode motions of the backbone chains of resins, and the γ-dispersion, to the molecular motions of long alkyl chains. If certain additives are mixed into the varnishes before curing, microphase separation takes place during the reactions. The resins finally obtained have a peculiar physical structure in which rubber particles are dispersed throughout a matrix phase as confirmed by scanning electron-microscopic analysis and viscoelastic behavior. 相似文献