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排序方式: 共有871条查询结果,搜索用时 312 毫秒
81.
Mehrdad Rafat May Griffith Malik Hakim Lea Muzakare Frank Li K.C. Khulbe Takeshi Matsuura 《应用聚合物科学杂志》2007,106(3):2056-2064
Argon plasma treatment enhanced the attachment of epithelial cells to a collagen‐based artificial cornea crosslinked using glutaraldehyde (GA) and glutaraldehyde‐polyethylene oxide dialdehyde (GA‐PEODA) systems. The epithelialization of untreated and treated surfaces was evaluated by the seeding and growth of human corneal epithelial cells. Characterization of polymer surface properties such as surface hydrophilicity and roughness was also made by contact angle measurement and atomic force microscopy, respectively. Contact angle analysis revealed that the surface hydrophilicity significantly increased after the treatment. In addition, AFM characterization showed an increase in surface roughness through argon plasma treatment. Based on the biological and surface analysis, argon plasma treatment displays promising potential for biocompatibility enhancement of collagen‐based artificial corneas. It was also found that the cell attachment to artificial cornea surfaces was influenced by the combined effects of surface chemistry (i.e., surface energy), polymer surface morphology (i.e., surface roughness), and polar interactions between functional groups at the polymer surface and cell membrane proteins. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
82.
The switching current for the device is about 90 mA at all in-range wavelengths. Its broad wavelength range is suitable for optical signal-processing applications in wavelength-division multiplexing transmission systems. High coupling efficiency to a single-mode fiber is achieved by using a small-Δ waveguide structure with carrier blocking layers. The effective refractive index change in the waveguide per unit of the injected current density is doubled by the carrier blocking layers without reducing coupling efficiency 相似文献
83.
Y Fujimoto H Matsuura K Kawabata K Takahashi N Tayama 《Canadian Metallurgical Quarterly》1997,100(11):1401-1407
The Swallowing Ability Scale (SAS) has been recently reported by us. This scale is a new method to assess dysphagia after therapy for oral and oropharyngeal cancer. The preliminary results on 23 patients showed that the scale was reliable and sensitive to functional differences across a broad spectrum of oropharyngeal dysphagia after therapy. This paper confirmed the above facts in 73 oral and oropharyngeal cancer patients who were treated in two hospitals between 1995 and 1996. As stated in the previous paper, SAS consists of a 2-step questionnaire: the MTF score and the Dysphagia score. The MTF score is a simple and practical assessment tool consisting of three subscales: 1) Method of intake, 2) Time of intake, and 3) Food. The Dysphagia score is a relevant assessment tool for defining patients' anatomic or physiologic swallowing disorders. In 40 patients with wide resection of the tongue, the Dysphagia score (p < 0.05) and the MTF score (p < 0.01) were significantly decreased. And we found a correlation between the MTF score and the Dysphagia score (r = 0.78, p < 0.001) in 73 patients. The usefulness of the SAS will be further studied for the assessment of rehabilitation to improve postoperative dysphagia. 相似文献
84.
M. Khayet A.O. Imdakm T. Matsuura 《International Journal of Heat and Mass Transfer》2010,53(7-8):1249-1259
A Monte Carlo (MC) simulation model is developed to study heat and mass transfer through hydrophobic membranes applying direct contact membrane distillation (DCMD) process. In this study, the membrane pore space is described by a three-dimensional network model of inter-connected cylindrical pores with distributive pore size. Vapor flux through membrane pores is described by gas transport mechanism(s) based on the kinetic theory of gases. The present MC model can take into consideration the influence of temperature polarization phenomenon, membrane physical properties including pores interconnectivity and the DCMD fluid dynamic conditions. The developed model can simultaneously predict the DCMD process vapor flux and membrane surface temperatures, contrary to other models in which one of them has to be given in order to solve the other. The model is comprehensive in its approach and does not involve any adjustable parameter. The simulated results were compared with the experimental ones of different membranes and the comparisons were found to be in excellent qualitative and quantitative agreement. 相似文献
85.
86.
Yuko Hamabe Ryoko Matsuura Akinori Jyo Masao Tamada Akio Katakai 《Reactive and Functional Polymers》2009,69(1):1-8
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin. 相似文献
87.
Naoki Mizuta Kiyotaka Matsuura Soshu Kirihara Yoshinari Miyamoto 《Materials Science and Engineering: A》2008,492(1-2):199-204
Feasibility of a new method of titanium aluminide coating on titanium surface based on a reaction between aluminum liquid beads and the surface of titanium substrate has been studied using a computer-aided three-dimensional microwelder (3DMW) designed by the present authors. A predetermined length of thin aluminum wire was fed onto the substrate surface, and a spark was stricken from a thin electrode of a W-Ce2O3 alloy to make a small aluminum liquid bead on the substrate surface and to simultaneously melt a small area of the substrate surface beneath the bead. All conditions including the length of the wire feeding, the position of the electrode, electric power, etc. had been programmed beforehand. The liquid bead containing aluminum and titanium rapidly solidified on the titanium substrate surface producing titanium aluminides on it. Repetition of the aluminum wire feeding, the electrode positioning and the spark striking produced a coating layer consisting of sub-layers of TiAl3, TiAl and Ti3Al from the surface side to the substrate side. Vickers hardness and wear resistance of the coated sample were remarkably improved. 相似文献
88.
Liposome‐Based in Vitro Evolution of Aminoacyl‐tRNA Synthetase for Enhanced Pyrrolysine Derivative Incorporation 下载免费PDF全文
Dr. Atsuko Uyeda Dr. Takayoshi Watanabe Dr. Yasuhiko Kato Prof. Hajime Watanabe Prof. Tetsuya Yomo Prof. Takahiro Hohsaka Dr. Tomoaki Matsuura 《Chembiochem : a European journal of chemical biology》2015,16(12):1797-1802
Methanosarcina species pyrrolysyl‐tRNA synthetase (PylRS) attaches Pyl to its cognate amber suppressor tRNA. The introduction of two mutations (Y384F and Y306A) into PylRS was previously shown to generate a mutant, designated LysZ‐RS, that was able to attach N‐benzyloxycarbonyl‐L ‐lysine (LysZ) to its cognate tRNA. Despite the potential of LysZ derivatives, further LysZ‐RS engineering has not been performed; consequently, we aimed to generate LysZ‐RS mutants with improved LysZ incorporation activity through in vitro directed evolution. Using a liposome‐based in vitro compartmentalization (IVC) approach, we screened a randomly mutagenized gene library of LysZ‐RS and obtained a mutant that showed increased LysZ incorporation activity both in vitro and in vivo. The ease and high flexibility of liposome‐based IVC should enable the evolution of not only LysZ‐RS that can attach various LysZ derivatives but also of other enzymes involved in protein translation. 相似文献
89.
Mahdi Pourafshari Chenar Houman Savoji Mohammad Soltanieh Takeshi Matsuura Shahram Tabe 《Korean Journal of Chemical Engineering》2010,27(6):1876-1881
Impurities such as hydrogen sulfide, water vapor and heavy hydrocarbons in natural gas have considerable effects on the membrane
performance. Small amounts of condensable and polymer soluble components in the feed gas cause swelling or plasticization
of glassy membranes, leading to a reduction in membrane selectivity. In the present research the influence of ethane was investigated
on the permeance and selectivity of two commercially available hollow fiber membranes, namely Cardo-type polyimide and PPO
hollow fibers for CO2/CH4 separations. It was concluded that the gas mixture permeation rate was increased in the presence of C2H6. However, the CO2/CH4 separation factors remained almost the same in the presence and absence of the C2H6. 相似文献
90.
Kohei Urasaki Ken-ichiro Endo Tomoki Takahiro Ryuji Kikuchi Toshinori Kojima Shigeo Satokawa 《Topics in Catalysis》2010,53(7-10):707-711
Selective methanation of CO in the reformate gas (CO/CO2/H2/H2O = 0.175/17.9/70.9/11.1) proceeded over Ru catalysts supported on metal oxides and zeolites. CO was selectively methanated at wide temperature ranges (200–275 °C) over Ru/γ-Al2O3, Ru/TiO2 Ru/H-Y and Ru/H-beta catalysts. Higher Ru contents in Ru/γ-Al2O3 improved the selective CO methanation rate. 相似文献