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141.
n‐Type π‐conjugated polymers comprising a 1,2,4‐triazole ring substituted by a benzo‐15‐crown 5‐ether (benzo15C5) subunit at the 4‐position of the 1,2,4‐triazole ring and n‐type aromatic rings such as pyridine‐2,5‐diyl and 2,1,3‐benzothiadiazole‐4,7‐diyl rings were synthesized by organometallic polycondensation. The UV‐visible spectra of the polymers exhibited absorption maxima (λmax values) at a longer wavelength than that exhibited by 3,5‐bis(2‐bromopyridyl)‐4‐benzo15C5‐1,2,4‐triazole, revealing that their π‐conjugation system was expanded along the polymer chain. The polymers with the benzo15C5 subunit underwent an electrochemical reduction (n‐doping), and the corresponding oxidation (n‐dedoping) occurred at an unusually high potential in an acetonitrile solution of NaClO4; the factor responsible for the unusually high oxidation potential was the stabilized n‐doping state that was attributed to the inclusion of Na+ in the 15C5 ring. The polymers with the benzo15C5 subunit exhibited a considerably higher stability of the n‐doping state in air than did those without this subunit. Copyright © 2012 Society of Chemical Industry 相似文献
142.
Zhang Lan Takei Ryohei Lu Jian Makimoto Natsumi Itoh Toshihiro Kobayashi Takeshi 《Microsystem Technologies》2022,28(6):1389-1397
Microsystem Technologies - An aluminum-nitride (AlN) based microelectromechanical system (MEMS) vibration device sensor with a power-harvesting function is developed. We aimed at realizing a... 相似文献
143.
Stephen J. Grunzinger Masatoshi WatanabeKiyotaka Fukagawa Ryohei KikuchiYoichi Tominaga Teruaki HayakawaMasa-aki Kakimoto 《Journal of power sources》2008
Hyperbranched poly(ether sulfone) polymers having sulfonyl chloride end-groups is blended at up to 30 w% with linear poly(ether ether ether sulfone)s and a two-phase system is generated via spinodal decomposition upon drying from a DMAc solution. Conversion of the end-groups from sulfonyl chloride to sulfonic acid is accomplished using 16 M H2SO4 that is also believed to introduce additional sulfonic acid groups at the interface of the linear polymer. The blend films before and after conversion to sulfonic acid have similar tensile strengths as films composed of solely linear polymer (yield stress >40 MPa and Young's modulus >3 GPa m). These films are designed to test the viability of hyperbranched polymers as fuel cell membranes. Proton conductivities of up to 0.03 S cm−1 are observed at 80 °C and 90% R.H indicating a good potential for use of hyperbranched polymers as a proton conduction material. 相似文献
144.
Y Okada Y Mizutani M Kawakita A Terai Y Kakehi T Terachi O Yoshida T Kanba T Okabe A Hamaguchi T Tomoyoshi 《Canadian Metallurgical Quarterly》1997,43(3):191-196
Demodex folliculorum has been demonstrated with an elevated frequency in patients with blepharitis, and is thought to cause therapy-resistant blepharitis. This paper presents the germ spectrum of patients with blepharitis and demodex and discusses the efficiency of a specific therapy. METHODS: In all, 3152 cilia from 139 patients with blepharitis (38% blepharitis, 44% blepharoconjunctivitis, others) and 108 persons with quiet eyes were examined for demodex. Smears n = 125, from the conjunctive of symptomatic patients were investigated for bacteria, 3 weeks of therapy with mercury ointment, 2%: Lindan, cortisone (prednisolone, dexamethasone, hydrocortisone, fluorometholone) or antibiotics after antibiogram (gentamicin, kanamicin, neomicin, erythromicin, ofloxacin, polymyxin-B, colistin) followed in all Demodex-positive blepharitis patients (n = 41). RESULTS: Demodex was found in 52% (62/139) of patients with chronic blepharitis, as against 20% (3/15) of those with acute blepharitis (statistically significant difference, chi 2-test, alpha = 2.5%) and in 29% of quiet eyes (statistically significantly less, alpha = 2.5%, chi 2-test). Gram-positive cocci were isolated from 79% of 57 Demodex-positive patients with blepharitis and 72% of 68 Demodex-negative patients anaerobes in 39% and 37%, gram-negative rods in 11% and 3% (statistically significant difference for gram-negative rods, alpha = 5%, chi 2-test). Of the patients with Demodex, 25% apparently had no more parasites after mercury ointment, 2% (n = 8) and lindan (n = 5) and 15% after cortisone and antibiotics (n = 13). (The best and statistically very significant results (alpha = 1%) were those obtained with mercury ointment, 2%, and lindan: t-test for connected spot checks). CONCLUSIONS: Gram-positive and gram-negative bacteria grew more often in patients with Demodex. Demodex seems to be a mediator of chronic blepharitis; we recommend that mites be sought in cilia of chronic blepharitis patients. Mercury ointment, 2% and lindan proved efficient for specific therapy, the main problem being the laborious application and toxicity. 相似文献
145.
H Miwa T Murai R Ohkura A Nagahara H Watanabe T Terai S Watanabe N Sato 《Canadian Metallurgical Quarterly》1998,13(10):1039-1043
Most of the reported [13C]-urea breath test procedures use a test meal, which is believed to assist in the spread of the [13C]-urea solution into the entire stomach, as results without a test meal may mainly reflect urease activity in the antrum.Yet, procedures for the [13C]-urea breath test and interpretation of the obtained 13C excess value have not been well established. We carried out the present study to validate the usefulness of the [13C]-urea breath test in fasting subjects and to establish cut-off values. [13C]-Urea breath tests were performed on 258 Helicobacter pylori-positive and 151 -negative subjects (247 H. pylori positive and 26 negative prior to any H. pylori cure treatment and 125 H. pylori negative and 11 positive after undergoing H. pylori cure treatment). The breath test procedure was performed under the following conditions: an 8 h fast, mouth washing before and after dosing, administration of 100 mg [13C]-urea, collection of breath sample in a plastic bag, a baseline and a 20 min sampling point and subject in a sitting position. Delta-13C at the 20 min sampling point in H. pylori-positive and -negative subjects was 31.0+/-1.25 and 1.6+/-0.11%, respectively. Although the mean delta13C value was greatest in duodenal ulcer or ulcer scar patients, there were no significant differences among mean delta13C values in the various diseases. From Receiver Operator Characteristic curves and calculation of accuracy of the test, a cut-off value of 5.0% is considered to be appropriate for diagnosis of H. pylori infection, which provides 96.7% specificity and 96.5% sensitivity, suggesting that the [13C]-urea breath test in the fasting state is as effective in detecting the presence of H. pylori as other reported methods. 相似文献
146.
Takamitsu Isono Takeshi Fukuda Kouji Nakagawa Reo Usui Ryohei Satoh Eiji Morinaga Yu Mihara 《Journal of the Society for Information Display》2007,15(2):161-166
Abstract— SnO2 is considered to be a promising alternative material for indium tin oxide (ITO), which is used for thin‐film transparent electrodes in flat‐panel displays (FPDs) and is facing a serious indium depletion problem. However, annealing processes in the manufacture of plasma‐display panels (PDPs), which are major FPDs, cause high resistivity in SnO2 films. To obtain lower resistivity after the annealing processes, the relationship between deposition conditions and resistivity and the influences of annealing on resistivity, both theoretically and experimentally, were investigated. As a solution, a method involving the formation of a coating of SiO2 on SnO2 is proposed, and a SnO2 resistivity as low as 6.60 × 10?5 Ω‐m was obtained after annealing. 相似文献
147.
Theoretical Estimation of Machined Surface Profile Based on Cutting Edge Movement and Tool Orientation in Ball-nosed End Milling 总被引:1,自引:0,他引:1
This paper presents the theoretical estimation method of machined surface profile without actual machining in ball-nosed end miling. The fundamental simultaneous equations of identifying the cusp height at any point of a workpiece in the simulated surface have been successfully derived from the geometric relationship between the cutting edge movement and the normal line at the point. By the numerical calculation, the machined surface profile can be estimated and illustrated graphically. It was found that the maximum and minimum cusp heights exist in a narrow range of tool orientation less than 3 degrees near the normal direction. 相似文献
148.
Effects of fullerene derivatives on the gas permeability of thermoplastic polyurethane elastomers 下载免费PDF全文
In an effort to improve the gas barrier properties of thermoplastic polyurethane (TPU) elastomers, fullerene derivatives were added as fillers, and the resulting O2 and CO2 permeabilities were analyzed. The addition of 5 wt % polyhydroxylated fullerene {fullerenol [C60(OH)n] mixture, where n = 6–12} decreased the gas permeability by approximately 10–20%. According to the hole volumes computed with the results from positron annihilation lifetime spectroscopy, the addition of fullerene derivatives did not produce any changes in the hole volumes of the TPUs. Thus, the reduction in the TPU gas permeability was not caused by changes in the hole volumes. Instead, an inhibited diffusion of gas molecules by fullerene particles was deduced as the cause of the decrease in gas permeability from changes in the diffusion coefficient with temperature. The addition of urethanized fullerene, prepared through the chemical modification of fullerenol, markedly affected the TPU gas barrier properties. As compared to fullerenol addition, the gas barrier properties improved approximately fourfold for O2 and approximately fivefold for CO2. These results suggest that the dispersability of urethanized fullerene in TPU was higher than that of fullerenol. We found that the gas barrier properties were independent of the structure of polyol. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39986. 相似文献
149.
Tanaka N Sasao M Terai K Okamoto A Kitajima S Yamaoka H Wada M 《The Review of scientific instruments》2012,83(2):02B115
Proof of principle experiments of neutral helium beam production for alpha particle diagnostics was carried out on a test stand. Negative helium ions were produced in the Li charge exchange cell, in which stable and long time operation was possible. He(-) beam was accelerated to 157 keV. Finally, He(0) beam was successfully produced after the flight in the drift-tube through the auto-electron-detachment process from He(-) to He(0). A neutral beam detector using a pyroelectric device was also developed to measure He(0) beam intensity. The metastable component in the neutral helium beam was found to be less than 2%. 相似文献
150.
Rina Maeda Teruaki Hayakawa Masatoshi Tokita Ryohei Kikuchi Jun Kouki Masa-aki Kakimoto Hiroaki Urushibata 《Reactive and Functional Polymers》2009,69(7):519-529
Well-defined double liquid crystalline side-chain type block copolymers (DLC-BCPs) were synthesized by nitroxide-mediated living free radical polymerization (NMP) of two different types of styrene monomers containing liquid crystalline moieties. The molecular weights and compositions were controlled by changing the polymerization time and/or the feed amount of the monomers. The bulk morphologies were studied using wide-angle X-ray scattering (WAXS), small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). DLC-BCPs were favored to form microphase-separated lamellar structures over a wide range of volume fractions. By controlling the annealing conditions, further higher-ordered hierarchical nanostructures were obtained with a long-range alignment, in which the semi-crystalline side-chains were oriented parallel to the interface of microphase-separated lamellar structure. Thin film morphology was investigated using atomic force micrography (AFM). The formation of lamellar nanostructure with a long-range alignment vertically oriented to the silicon wafer substrate was achieved by simple thermal annealing. 相似文献