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61.
Yoshiko Yamazaki Toru Matsunaga Aya Ichinokawa Yoko Fujishiro Emi Saito Takao Sato 《应用聚合物科学杂志》2009,114(5):2764-2768
In the zwitterionic polymer gel which has cationic and anionic groups inside, it forms a complex to producing stability by adding thermal energy. We reported the behavior induced by the ionic interaction of them and the impact that a nonionic surfactant could exert on the complex formation. We had heating experiments of the zwitterionic polymer gel in PBS with a nonionic surfactant added. We analyzed DSC and measured the diameter, stress and flexure of heated the gel. As the result, it has been demonstrated that formation of strong ionic interactions inside the gel can be achieved by heating them in a solution containing the nonionic surfactant. It has been also demonstrated that the ratio of bound water is increased within the gel, promising an enhanced strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
62.
Reactive sputtering techniques have been widely used for forming compound thin films. In this study, the time-dependent variation of the target mode of an Al-O2 system was investigated by measuring the target voltage for various reactive O2 gas flow ratios and presputtering (i.e., sputtering in pure Ar gas to clean the target surface) times. The Al target remains in metallic mode for a certain period of time after being exposed to an Ar-O2 plasma before it begins to be oxidized. This period increases with decreasing O2 flow ratio and with increasing the presputtering time. It is considered that the period is caused by the gettering of O2 gas by Al films deposited on the substrate and the chamber wall during presputtering. 相似文献
63.
Hiroyuki Fujishiro Manabu Ikebe Yuzo Shibazaki 《Journal of Low Temperature Physics》1999,117(5-6):1181-1185
The thermal conductivity has been measured for La
2-X
Sr
X
CuO
4
and La
1.85
Sr
0.15
Cu
0.98
M
0.02
O
4
(M; Zn, Ni). The characteristic enhancement in below T
c
was confirmed for La
1.85
Sr
0.15
CuO
4
. The phonon scattering mechanisms were analyzed in detail and the electron-phonon coupling constant was estimated to be 0.05. The enhancement becomes indetectable on Zn or Ni substitution for Cu, which indicated survival of the phonon scattering by charge carriers down to lower temperatures as a result of reduced T
c
. 相似文献
64.
Takahashi M Iwakiri K Sotoyama M Higuchi S Kiguchi M Hirata M Hisanaga N Kitahara T Taoda K Nishiyama K 《Applied ergonomics》2008,39(5):597-604
Nursing home caregivers (n=775; 604 women; mean age 33.6 years) were studied to examine how work schedules affect their sleep. The shift group (n=536) worked under a rotating two-shift system (n=365), a rotating three-shift system (n=66), or other types of shifts (n=78). The non-shift group included 222 caregivers. Participants completed a questionnaire about working conditions, sleep problems, health, lifestyle, and demographic factors. The two-shift caregivers reported the highest levels of difficulty initiating sleep (DIS, 37.6%), insomnia symptoms (43.0%), and poor quality of sleep (24.9%) among the groups. Adjusted odds ratios for these problems were significantly greater for the two-shift caregivers than for non-shift counterparts: DIS (odds ratio 2.86, 95% confidence interval 1.57-5.20), insomnia symptoms (2.33, 1.36-4.02), and poor sleep quality (2.15, 1.09-4.22). Our data suggest that working under a rotating two-shift system, which has a longer night shift, is associated with an elevated risk of sleep problems for nursing home caregivers. 相似文献
65.
66.
Ohmuro K. Fujishiro H.I. Itoh M. Nakamura H. Nishi S. 《Microwave Theory and Techniques》1991,39(12):1995-2000
Characteristics of the pseudomorphic inverted HEMT (P-I-HEMT) are compared with those of the pseudomorphic HEMT. Both devices were fabricated in enhancement mode by the same process. P-I-HEMT shows a higher maximum transconductance of 590 mS/mm, and higher K -value of 600 mS/Vmm at a threshold voltage of O V, and better pinch-off characteristics than its counterpart. Noise characteristics of P-I-HEMT are reported. Lower noise figure (1.0 dB at 18 GHz) was obtained in the P-I-HEMT. It is concluded that the P-I-HEMT shows far better noise characteristics than the other at low drain voltage and current 相似文献
67.
Akira?HaraguchiEmail author Midori?Akioka Sawahiko?Shimada 《Nutrient Cycling in Agroecosystems》2005,71(1):101-108
The chemical properties of peat pore water in the basin of the Sebangau River and Lahei district, Central Kalimantan, Indonesia, were studied. We analyzed major ions, pH, electrical conductivity (EC) and redox potential (Eh) of the peat pore water with reference to their vertical profile. We evaluated the contribution of sulfates to the acidi.cation of peat by including data from Furen mire, eastern Hokkaido, Japan. The coastal peat of Furen mire and the peat in Paduran in the lower basin of the Sebangau River included extraordinarily high concentrations of sulfates (> 1000 mg/l) compared to the peat in the middle and upper basins of the river (< 10 mg/l). High concentrations of sulfates, however, did not lead to a low pH for the peat. The present findings suggest that the acidification of the peat pore water is subject to the production of organic acids originating from peat decomposition, rather than the production of sulfuric acid produced by pyrite oxidation in the underlying mineral sediments. 相似文献
68.
The effect of Pt ion plating on the high cycle axial fatigue life of Ti-6Al-2Sn-4Zr-2Mo specimens was studied at room temperature
and 455 °C. Unlike other coatings, the plated material tested in this work showed an increase in fatigue strength when compared
to uncoated material. The fatigue strength improvement was greater at 455 °C than at room temperature. Coated specimens cycled
close to the fatigue limit at 455 °C demonstrated the highest improvement, which was associated with subsurface fatigue crack
initiation. The uncoated specimens, tested under similar conditions, failed by cracking at the surface. Sectioning analysis
showed no defects in the subsurface initiation sites. The initiation was related to groups of similarly aligned coarse α platelets.
It is suggested that the Pt ion plating caused some surface hardening as well as oxidation resistance at elevated temperatures
leading to the suppression of surface crack initiation. 相似文献
69.
70.
Fujishiro Y Sugimori A Okuwaki A Sato T 《Journal of materials science. Materials in medicine》2001,12(4):333-337
Hydroxyapatite was coated on various substrates such as 12 mol % ceria-doped tetragonal zirconia (12Ce-TZP), 3 mol % yttria-doped tetragonal zirconia (3Y-TZP), alumina, monetite coated titanium (Ti/CaHPO4) and calcium titanate coated titanium (Ti/CaTiO3) via hydrothermal reactions of Ca(edta)2- and 0.05 M NaH2PO4 at initial pH 6 and 160–200 °C for 0.5–6 h. Rod-like particles of hydroxyapatite precipitated to form film on the substrates above 160 °C. The morphology of the film changed significantly depending on the characteristics of substrate, i.e. hydroxyapatite entirely coated the surfaces of 12Ce-TZP, Ti/CaHPO4 and Ti/CaTiO3 plates, but sparsely deposited on 3Y-TZP and Al2O3 plates. Film thickness increased with time (ca. 20 and 90 m on 12Ce-TZP plates for 0.5 and 6 h, respectively, at pH 6 and 200 °C). The adhesive strength of the film for the substrate was in the order, 12Ce-TZP/hydroxyapatite(28 MPa) > Ti/CaTiO3/hydroxyapatite (22 MPa) > Ti/CaHPO4/hydroxyapatite (9 MPa). © 2001 Kluwer Academic Publishers 相似文献