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201.
Hitoshi Kubota Noriyasu Nagaoka Ryoichi Katakai Masaru Yoshida Hideki Omichi Yasuo Hata 《应用聚合物科学杂志》1994,51(5):925-929
Photografting of N-isopropylacrylamide (NIPAAm) on ethylene–vinyl alcohol copolymer films (thickness = 15,20, and 25 μm) and low-and high-density polyethylene films (thickness = 30 μm) was carried out at 60°C in a water medium. Xanthone was used as a photoinitiator by coating it on the film samples. The resultant NIPAAm-grafted films exhibited a temperature-responsive character, which was evaluated by measuring a dimensional change of the grafted films. The grafted films swelled and shrank in water at temperatures lower and higher than around 30°C, respectively. The character was found to be reversible between 0 and 50°C. It was observed that the extent of the character is largely influenced by film thickness, location of NIPAAm-grafted chains, and crystallinity of film substrate. © 1994 John Wiley & Sons, Inc. 相似文献
202.
The reaction of 5-amino-2,3-dicyano-1,4-naphthoquinone (1) with arylamines gave 5-amino-8-arylamino- (2), 5,8-bis(arylamino)- (3), and 5-hydroxy-8-arylamino-2,3-dicyano-1,4-naphthoquinone (4) together with 5-amino-2-arylamino-3-cyano- (5) and 5-amino-2-cyano-3-aryl-amino-1,4-naphthoquinone (6). It is proposed that the initial quinone-quinoneimine tautomerism of 1 to 4-hydroxy-2,3-dicyano-5-imino-1,5-naphthoquinone 7 facilitates the 8-arylamination. Some derivatives of 2 have good properties as dyes for optical information-recording media for semiconductor lasers. 相似文献
203.
Simulation of photoelectric conversion in the photosynthetic reaction centre by a monomolecular layer assembly was successfully attained by using a newly synthesized linear A-S-D triad as a charge separation unit and an antenna pigment for light harvesting. The synthetic amphiphilic triad molecule has three functional moieties within a molecule, i.e. a hydrophilic electron acceptor viologen (A), a hydrophobic sensitizer perylene (S) and a hydrophobic electron donor ferrocene (D) moiety. The amphiphilic antenna molecule has a light-harvesting pyrene (H) moiety in the middle of the alkyl chain of fatty acid. Because of overlap of the emission spectrum of the antenna pyrene and the absorption spectrum of the sensitizer perylene moiety of the triad, light energies harvested by the antenna molecules were efficiently transferred to the sensitizer moiety of the triad and finally converted to electrical energies via multistep electron transfer across the monolayer through the charge separation unit of the triad molecule in the highly oriented monolayer assembly. 相似文献
204.
T Komiya 《Canadian Metallurgical Quarterly》1997,64(1):67-84
The purpose of this study was to investigate the influence of 3,3-dimethyl-1-phenyltriazene (DMPT) on development of craniofacial structures in mouse fetus. (1) Pregnant C57BL/6 mice were treated with 30 mg/kg DMPT injection on days 10.5 approximately 13.5 of gestation. The fetuses were analyzed on day 15.0. The incidence of micrognathia was formed 100% in the treated group on days 10.5 and 11.0, and then decreased remarkably after day 11.5. This result suggested that the critical period of micrognathic development is days 10.5 approximately 11.0. (2) The fetuses, injected 30 mg/kg DMPT on day 10.5, were sacrificed on days 11.0 approximately 18.0. Their heads were used for the following histomorphological analyses: 1. clearing and Alcian blue-alizarin red double staining and 2. lateral graphic reconstruction using serial frontal sections. Dysmorphology of the anterior portion of Meckel's and nasal septal cartilage became evident after day 13.0, however, nasal capsule cartilage was hardly affected. It was concluded that hypoplastic Meckel's cartilage, caused by the administration of DMPT, induced mandibular dysmorphogenesis. 相似文献
205.
R Suzuki H Sakamoto H Yasukawa M Masuhara T Wakioka A Sasaki K Yuge S Komiya A Inoue A Yoshimura 《Canadian Metallurgical Quarterly》1998,17(17):2271-2278
We have reported JAK-signaling modulators, CIS1 (cytokine-inducible SH2 protein-1), CIS3 and JAB (JAK2 binding protein), which are structurally related. In M1 myeloid leukemia cells, CIS3 was induced by neither interleukin 6 (IL6) nor interferon gamma (IFNgamma), while JAB was induced strongly by IFNgamma and slightly by IL6 and leukemia inhibitory factor (ILF). Forced expression of CIS3 and JAB in M1 cells prevented IL6- or LIF-induced growth arrest and differentiation, even when their expression levels were comparable to endogenous ones in several cell lines such as HEL, UT-7, IFNgamma-treated M1, and CTLL2 cells. Pretreatment of parental M1 cells with IFNgamma but not IFNbeta resulted in suppression of LIF-induced STAT3 activation and differentiation, further supporting that physiological level of JAB is sufficient to inhibit LIF-signaling. However, unlike JAB, CIS3 did not inhibit IFNgamma-induced growth arrest, suggesting a difference in cytokine specificity between CIS3 and JAB. CIS3 inhibited STAT3 activation with slower kinetics than JAB and allowed rapid c-fos induction and partial FcgammaRI expression in response to IL6. In 293 cells, CIS3 as well as JAB bound to JAK2 tyrosine kinase domain (JH1), and inhibited its kinase activity, however, the effect of CIS3 on tyrosine kinase activity was weaker than that of JAB, indicating that CIS3 possesses lower affinity to JAK kinases than JAB. These findings suggest that CIS3 is a weaker inhibitor than JAB against JAK signaling, and JAB and CIS3 possess different regulatory roles in cytokine signaling. 相似文献
206.
Paresh L. Dhepe Masataka Ohashi Shinji Inagaki Masaru Ichikawa Atsushi Fukuoka 《Catalysis Letters》2005,102(3-4):163-169
Mesoporous silicas are modified with sulfonic acid groups either by one-pot or by grafting method. In the hydrolysis of sucrose and starch, the sulfonated mesoporous silicas work as water-tolerant recyclable solid acid catalysts, showing higher conversion and turnover frequency than conventional Amberlyst-15, Nafion-silica and HZSM-5 catalysts. 相似文献
207.
Masaru Nakano Junzo Hasegawa Toshitaka Kuno Hiroshi Moribe Toshiaki Ikeda Mitsuo Koide Osamu Shiroshita Kazutoshi Sukigara 《野外机器人技术杂志》1985,2(3):277-288
TL-10, Toyoto Robot Language-10, is a BASIC-like robot language. It has functions that define locations and subroutine parameters, which are useful in the accumulation and the transference of robot applied technology. It also has functions to communicate with other computers such as those for vision systems. The important features are described and illustrated by examples. 相似文献
208.
Yoshiharu Shin Hideki Aoki Naoki Yoshiyama Masaru Akao Masaaki Higashikata 《Journal of materials science. Materials in medicine》1992,3(3):219-221
Hydroxyapatite ceramic (HAC) was studied for utilization as a percutaneous device to prevent exit-site and tunnel infection along peritoneal dialysis catheters. As a result, it was found that HAC had good compatibility with skin tissue compared with silicone rubber and glassy carbon. In the present study, the surface properties of HAC after long-term implantation in skin of dogs was evaluated by scanning electron microscopic observation, solubility and bending tests. At 12 weeks after implantation, the surface of HAC was eroded severely by body fluid or cells, and the grain boundaries were clearly relieved. Ingrowth and adhesion of collagen into the etched ditch of HAC were observed. At 12 months, the eroded surface had been tightly covered and adhered to by a collagenous layer in spite of ripping off the surrounding fibrous capsule. In solubility tests, HAC dissolved at the rate of 0.23 mg cm–2 HAC surface area per year. On the other hand, the bending strength decreased by about 10% at 4 weeks and scarcely decreased after that time. From these results, it was confirmed that the solubility of HAC produced tight contact and strong adhesion with skin tissue to prevent bacterial infection, and HAC was practical for a permanent percutaneous device. 相似文献
209.
There are many expert systems that use experimental knowledge for diagnostic analysis and design. However, there are two problems for systems using only experiential knowledge:
- unexpected problems cannot be solved and
- acquiring experiential knowledge from human experts is difficult.
- inheritance for representation of objects,
- new primitive representations to describe discontinuous change, and
- control features for effective reasoning.
210.
Taishi Yano Koichi Nishino Satoshi Matsumoto Ichiro Ueno Atsuki Komiya Yasuhiro Kamotani Nobuyuki Imaishi 《Microgravity science and technology》2018,30(5):599-610
This paper reports an overview and some important results of microgravity experiments called Dynamic Surf, which have been conducted on board the International Space Station from 2013 to 2016. The present project mainly focuses on the relations between the Marangoni instability in a high-Prandtl-number (Pr=?67 and 112) liquid bridge and the dynamic free surface deformation (DSD) as well as the interfacial heat transfer. The dynamic free surface deformations of large-scale liquid bridges (say, for diameters greater than 10 mm) are measured with good accuracy by an optical imaging technique. It is found that there are two causes of the dynamic free surface deformation in the present study: the first is the time-dependent flow behavior inside the liquid bridge due to the Marangoni instability, and the second is the external disturbance due to the residual acceleration of gravity, i.e., g-jitter. The axial distributions of DSD along the free surface are measured for several conditions. The critical parameters for the onset of oscillatory Marangoni convection are also measured for various aspect ratios (i.e., relative height to the diameter) of the liquid bridge and various thermal boundary conditions. The characteristics of DSD and the onset conditions of instability are discussed in this paper. 相似文献