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排序方式: 共有144条查询结果,搜索用时 15 毫秒
1.
RA Reinhardt MP Masada GK Johnson LM DuBois GJ Seymour AC Allison 《Canadian Metallurgical Quarterly》1993,20(7):514-519
Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively. 相似文献
2.
Kiyoaki Imoto Kohshin Takahashi Takahiro Yamaguchi Teruhisa Komura Jun-ichi Nakamura Kazuhiko Murata 《Solar Energy Materials & Solar Cells》2003,79(4):459-469
Here, we reported that a new carbon electrode prepared with an activated carbon was superior to a Pt sputtered electrode as the counter electrode of dye-sensitized solar cells. The photovoltaic performance was largely influenced by the roughness factor of carbon electrode. The open-circuit voltage increased by about 60 mV using the carbon counter electrode compared to the Pt counter electrode because of positive shift of the formal potential for I3−/I− couple. 相似文献
3.
C4+ and S4+-codoped titanium dioxide (TiO2) having a rutile phase was prepared. By doping C4+ and S4+ ions into a TiO2 lattice, the absorption edge of rutile TiO2 powder was largely shifted from 400 to 700 nm. 2-Methylpyridine and methyleneblue were photocatalytically oxidized at high efficiency on C4+ and S4+-doped TiO2 under visible light at a wavelength longer than 5 nm. 相似文献
4.
超导储能装置用GTO PWM电流型变流器模块方阵 总被引:14,自引:8,他引:6
本文提出一种GTOPWM电流型变流器模块的连接方法。N×N个变流器模块组成一个方阵,通过适当地设计调制信号和载波信号的相位,该方阵能够实现特大功率变换,且网侧谐波得到抑制。由于PWM主要用来实现功率的调节,因此GTO仅需工作在较低的开关频率。本方案只需用N个移相变压器,就能获得6N2脉波变流器的特性。通过仿真,将变流器模块方阵与经典变流器模块直接并列结构作了比较。 相似文献
5.
6.
Jia Sun Ming Zhang Zhi-Feng Wang Hai-Yan Chen Ye Chen Naoya Murakami Teruhisa Ohno 《稀有金属(英文版)》2019,(4)
Anatase titanium(Ⅳ) oxide(TiO_2) particles with exposed {001} and {101} facets were prepared by hydrothermal treatment of amorphous TiO_2 with H_2O_2-NH_3 solution. Crystal phase, shape, and size of TiO_2 particles are found to be greatly dependent on the ratio of H_2O_2-NH_3 solution. The prepared TiO_2 particles with specific exposed crystal faces show higher photocatalytic activity for acetaldehyde decomposition than commercial spherical TiO_2 particles. This result implies that recombination is prevented by spatial separation of redox sites in the particles because of selective migration of electrons and positive holes to specific exposed crystal faces and/or different reactivity of electrons and positive holes on the specific exposed crystal face. 相似文献
7.
Toshiki Tsubota Masaki Morita Sunao Kamimura Teruhisa Ohno 《Journal of Porous Materials》2016,23(2):349-355
Unconventional pretreatment, that is, delignification and the addition of guanidine phosphate, was performed for the synthesis of activated carbon having a high specific surface area from bamboo by physical activation. The values of the specific surface area, total pore volume, and average pore size depended on the amount of added guanidine phosphate and the CO2 activation time. The amount of the added guanidine phosphate under the optimum conditions for the highest specific surface area was much lower than that of the phosphorous acid chemical activator under conventional conditions. The N2 adsorption isotherms of all the samples were type I, which means that micropores were dominant. The pore sizes of the samples in this study were similar to that of the physically-activated carbon. Therefore, the activation process was presumed to be essentially not chemical, but physical. The relation between the yield and the specific surface area improved with the addition of guanidine phosphate. The reason for the improvement may be the change in the reactivity of the carbon material generated during the heating process. The maximum specific surface area was ca. 2000 m2 g?1, which is a high value for a physically-activated carbon. 相似文献
8.
Teruhisa Horita Haruo Kishimoto Katsuhiko Yamaji Manuel E. Brito Yueping Xiong Harumi Yokokawa 《Journal of power sources》2009,193(1):180-184
Reactivity of oxide scale on Fe-Cr alloy with Na-containing gases was examined to estimate the stability against sodium (Na): vapors of NaCl and Na2SO4 exposures with air flow at 1073 K. The identified reaction phases were Cr-Mn spinel, Cr2O3, and alloy from the X-ray diffraction of surface with no Na-reaction products. However, the protective oxide scales (Mn-Cr spinel and Cr2O3 layers) on the Fe-Cr alloy were partially decomposed by reacting with Na to form Na-compounds inside the oxide scale/alloy interfaces. In some parts, anomalous oxide scales were found around the oxide scale/Fe-Cr alloy interfaces, with forming Na-rich compounds: the compounds were distributed inner parts of oxide scales around oxide scale/alloy interfaces. The stability of oxide scales and degradation were discussed based on the observed distribution of elements. 相似文献
9.
Tatsuyuki Sagawa Etienne Boisnier Teruhisa Komatsu Karim Ben Mustapha Abdalla Hattour Naoko Kosaka 《International journal of remote sensing》2013,34(12):3051-3064
Remote sensing is widely used in coastal management. Lyzenga's model has been traditionally used to explain the relationship between bottom surface reflectance and the radiance level measured by satellite. Due to its central assumption, this model lacks accuracy compared with the other radiative transfer models. Nonetheless, it enables, with a single and simple equation, representation of the multiple optical processes taking place in coastal areas. Mapping processes associated with this model may include radiometric correction, a technique previously pointed out as a major driver of mapping accuracy. Radiometric correction is generally based on a depth-invariant index, efficient for clear waters (Jerlov water type I to II) but largely unsuitable when transparency decreases (Jerlov water type II to III). In order to overcome this problem, we developed a new index for radiometric correction, which combines bathymetry data with attenuation coefficients. The improved efficiency of our model with regard to the traditional depth invariant index was demonstrated through two case studies: Funakoshi Bay (Japan; Jerlov water type II) and the Gabes Gulf part located off Mahares (Tunisia; Jerlov water type II to III). 相似文献
10.
Natsuko Sakai Tatsuo Tsunoda Natsuo Fukumoto Isao Kojima Katsuhiko Yamaji Teruhisa Horita Masahiko Ishikawa Harumi yokokawa masayuki Dokiya 《Journal of Electroceramics》1999,4(1):121-128
The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La1-xCaxCrO3 were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr6+(d0) was detected in the grain boundaries whereas Cr3+(d3) and Cr4+(d2) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr2+-La0.75Ca0.25CrO3 system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr6+ at grain boundaries. 相似文献