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排序方式: 共有442条查询结果,搜索用时 15 毫秒
101.
Kiyoshi Sato Sadao Arai Takamichi Yamagishi Tomoaki Tanase 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o162-o164
In 8a‐azonia[6]helicene hexafluorophosphate or 8a‐azoniaphenanthro[3,4‐c]phenanthrene hexafluorophosphate, C25H16N+·PF6−, replacement of an outer bridgehead carbon of hexahelicene by a quaternary Nsp2 atom results in a geometrical change in the helical structure. The racemic heterohelicene forms homochiral columnar stacks through intermolecular π–π donor–acceptor interactions in the crystalline state. 相似文献
102.
Shota OKUNO Toshihiro YAMASHITA Kengo SHIRADO Kenta KAWAMITSU Kaede YAMABE Yutaro ONISHI Taichi OGAMI Hiroto KAYASHIMA 《Physical Therapy Research》2021,24(3):225
Objective: The study aimed to demonstrate the significance of early postoperative physical therapy interventions on clinical outcomes by determining the influence of the distance walked under the supervision of a physical therapist in the early postoperative period after liver cancer. Methods: All consecutive patients who underwent surgery for liver cancer between April 2018 and March 2020 were eligible for enrollment in the study. The total walking distance during physical therapy till the third postoperative day was examined. The clinical outcomes comprised duration of postoperative hospital stay, time to independent walking, and occurrence of postoperative complications. For data analysis, the patients were divided into two groups: those who walked more than the median total distance (the long-distance group) and those who walked less than the median distance (the short-distance group). We used propensity score matching to match the background characteristics between the groups. Results: Of the 65 patients who were eligible, 14 patients were included in the two groups each, after matching. The long-distance walking group had a significantly shorter hospital stay (9.0 days vs. 11.0 days, p=0.008) and a shorter time to independent walking (3.5 days vs. 7.5 days, p=0.019) than the short-distance walking group. There were no significant differences in postoperative complications between the two groups (7.1% vs. 42.8%, p=0.08). Conclusion: In the early postoperative period after liver cancer surgery, increasing the walking distance under the supervision of a physical therapist is important for improving clinical outcomes. Further prospective studies are needed to confirm the findings of this study. 相似文献
103.
Itaru Natori Kimio Imaizumi Hideyuki Yamagishi Miyuki Kazunori 《Journal of Polymer Science.Polymer Physics》1998,36(10):1657-1668
The relationship between the microstructure and the properties of poly(1,3-cyclohexadiene)s, obtained by living anionic polymerization with an alkyllithium/amine system, and their hydrogenated derivatives are reported. The 1,2-bond/1,4-bond molar ratio of poly(1,3-cyclohexadiene) was determined by measuring 2D-NMR with the H H COSY method. The glass transition temperature of poly(1,3-cyclohexadiene) was found to rise with an increase in the ratio of 1,2-bonds to 1,4-bonds or with an increase of the number average molecular weight. The 1,2-bond of the polymer chain gives a high flexural strength and heat distortion temperature. Hydrogenated poly(1,3-cyclohexadiene) has the highest Tg (231°C) among all hydrocarbon polymers ever reported. 1,3-Cyclohexadiene–butadiene–1,3-cyclohexadiene triblock copolymer and 1,3-cyclohexadiene–styrene–1,3-cyclohexadiene triblock copolymer have high heat resistance and high mechanical strength. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1657–1668, 1998 相似文献
104.
J. D. Margerum F. G. Yamagishi A. M. Lackner E. Sherman L. J. Miller C. I. Van Ast 《Liquid crystals》1993,14(2):345-350
The problems of photoinitiator contamination are addressed for the liquid crystal phase in polymer dispersed liquid crystal films formed by photopolymerization induced phase separation of liquid crystal from monomer solutions. Initiator contamination lowers the clearing point of the liquid crystal phase, and decreases the photostability and resistivity of the polymer dispersed liquid crystal. These problems are minimized by replacing the conventional photoinitiators with copolymerizable initiators which become incorporated in the polymer phase as it separates. Copolymerizable photoinitiators are studied and used to form polymer dispersed liquid crystals with higher clearing point liquid crystal phases, higher resistivity, and better photostability than polymer dispersed liquid crystals formed with conventional photoinitiators. These improvements provide very significant advantages for many polymer dispersed liquid crystal applications. 相似文献
105.
In the flow around a circular cylinder, a sudden decrease in the drag force occurs at a high Reynolds number, but the same
phenomenon occurs at a lower Reynolds number in the case where there exist grooves or roughness on the circular cylinder surface.
In this paper, in order to make clear the flow characteristics around a circular cylinder in the case of changing the shapes
of grooves, the drag coefficient, pressure distribution, velocity distribution and turbulent distribution were measured. Moreover
the flow around the cylinder was analyzed by applying the RNGk · ∈ turbulent model, and the surface flow pattern was investigated using the oil-film technique. From these results, it is clear
that the drag coefficient of a circular cylinder with triangular grooves decreases by about 15% compared with that of a circular
cylinder with arc grooves. 相似文献
106.
Synthesis of protein-silica hybrid hollow particles through the combination of protein catalysts and sonochemical treatment 总被引:1,自引:0,他引:1
Shiomi T Tsunoda T Kawai A Chiku H Mizukami F Sakaguchi K 《Chemical communications (Cambridge, England)》2005,(42):5325-5327
Hollow spherical particles with protein-silica hybrid shell structures have been synthesized through a combination of the catalytic activity of the protein and sonochemical treatment; the morphologies of the particles were controlled by varying the protein concentration. 相似文献
107.
Keiko Kohmoto Kengo Katayama Hiroyuki Narihisa 《Mathematical and Computer Modelling》2003,38(11-13):1325
The performance of the genetic algorithm (GA) for the graph partitioning problem (GPP) is investigated by comparison with standard heuristics on well-known benchmark graphs. In general, there is a case where a practical performance of a conventional genetic approach, which performs only simple operations without a local search strategy, is not sufficient. However, it is known that a combination of GA and local search can produce better solutions. From this practice, we incorporate a simple local search algorithm into the GA. In particular, the search ability of the GA is compared with standard heuristics such as multistart local search and simulated annealing, which use the same neighborhood structure of the simple local search, for solving the GPP. Experimental results show that the GA performs better than its competitors. 相似文献
108.
109.
L.B. Coleman F.G. Yamagishi A.F. Garito A.J. Heeger D.J. Dahm M.G. Miles J.D. Wilson 《Physics letters. A》1975,51(7):412-414
Electrical conductivity measurements and the unit cell of a semiconducting derivative of TTF-TCNQ are reported. 相似文献
110.