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81.
The mechanism of pore formation by selective decomposition of adamantane unit in an ABA‐type triblock copolymer derived from 4,4‐(hexafluoroisopropylidene)diphthalic anhydride‐2,3,5,6‐tetramethyl‐1,4‐phenylenediamine (6FDA‐TeMPD) and poly(2‐methyl‐2‐adamantylmethacrylate) (PMAdMA) was investigated on this basis. This study aims to developing a novel method of material design for high‐precision gas separation membranes and application to electric devices by improving dielectric constant. Scanning electron microscopy images showed that the membrane structure changed considerably after heating; the difference increased with the increase in adamantane content. Interestingly, the internal structure of Block(36 mol%6FDA‐TeMPD/64 mol%PMAdMA) membrane was almost unchanged although its surface structure was changed. These results suggest that the mechanism of formation of porous membrane involves the decomposition of adamantane unit from surface. In addition, more adamantane units inside the membrane were discharged to the surface of the membrane through a path formed by decomposed adamantane units. POLYM. ENG. SCI., 56:1191–1200, 2016. © 2016 Society of Plastics Engineers  相似文献   
82.
The histone methyltransferase SET7/9 methylates not only histone but also non‐histone proteins as substrates, and therefore, SET7/9 inhibitors are considered candidates for the treatment of diseases. Previously, our group identified cyproheptadine, used clinically as a serotonin receptor antagonist and histamine receptor (H1) antagonist, as a novel scaffold of the SET7/9 inhibitor. In this work, we focused on dibenzosuberene as a substructure of cyproheptadine and synthesized derivatives with various functional groups. Among them, the compound bearing a 2‐hydroxy group showed the most potent activity. On the other hand, a 3‐hydroxy group or another hydrophilic functional group such as acetamide decreased the activity. Structural analysis clarified a rationale for the improved potency only by tightly restricted location and type of the hydrophilic group. In addition, a SET7/9 loop, which was only partially visible in the complex with cyproheptadine, became more clearly visible in the complex with 2‐hydroxycyproheptadine. These results are expected to be helpful for further structure‐based development of SET7/9 inhibitors.  相似文献   
83.
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009  相似文献   
84.
We propose in this paper an inference method called Bottom Generalization for Inductive Logic Programming (ILP, for short). We give an inference procedure based on it, and prove that a hypothesis clauseH is derived by the procedure from an exampleE under a background theoryB iffH subsumesE relative toB in Plotkin’s sense. The theoryB can be any clausal theory, and the exampleE can be any clause which is not implied byB. The derived hypothesisH is a clause, but is not always definite. The result is proved by defining a declarative semantics for arbitrary consistent clausal theories, and showing that SB-resolution, which was originally introduced by Plotkin, gives their complete procedural semantics. We also show that Bottom Generalization is more powerful than both Jung’s method based on theV-operator and Saturant Generalization by Rouveirol, but not than Inverse Entailment by Muggleton. At the ILP ’97 workshop we called our inference method “Inverse Entailment,” but we have renamed it “Bottom Generalization” because we found that it differs from the original definition of Inverse Entailment. The main part of this work was accomplished while the author was visiting the Artificial Intelligence Group, Department of Computer Science, Technical University Darmstadt, Germany. Akihiro Yamamoto, Dr.: He is an Associate Professor of the Division of Electronics and Information Engineering at Hokkaido University. He received the B.S. degree from Kyoto University in 1985, and the M.S. and Dr.Sci. degrees from Kyushu University in 1987 and 1990 respectively. He was a guest researcher of Oxford University Computing Laboratory, the United Kingdom, from January 1996 to March 1996, and of Department of Computer Science at Technical University Darmstadt, Germany, from June 1996 to May 1997. His present interests include the application of Logic Programming and Theorem Proving to Machine Learning.  相似文献   
85.
86.
The microstructure of a thermal shielding material affects its thermal conductivity and mechanical property. In this study, the effects of the sintering temperature and the polymethyl methacrylate powder as a pore-former on the microstructure of a sintered porous yttria-stabilized zirconia (YSZ), which is used as a durable thermal shielding material, were investigated. It became clear that the microstructure of the sintered YSZ could be controlled by the particle size and the amount of the pore-former and the sintering temperature. The effect of the yttria amount in the YSZ on the microstructure was also clarified.  相似文献   
87.
Diffusion kinetics of three dyes in nematic liquid crystals are studied with single-molecule fluorescence autocorrelation spectroscopy. Markedly large anisotropy was observed in the diffusion coefficient and structure of diffusion molecules showed no marked effect on the anisotropy.  相似文献   
88.
Summary Deuterium NMR measurements have been performed for dimer liquid crystals (DLC) having structures such as NC-O(CH2)nO-CN (CBA) with n=9, 10. Fully deuterated CBAs with n=9 and 10 exhibit, respectively, three and four splittings in the D-NMR spectra. By using partially deuterated samples, the signals corresponding to the largest splittings were found to include contributions from the - and -CD2 groups. The origins of the rest of the signals were elucidated by the RIS method previously established. Characteristic properties of the nematic mesophase were estimated for CBA-10. The results were found to be consistent with those of the previous analysis on Griffin et al.'s DLC.  相似文献   
89.
High-energy proton irradiation (380 keV and 1 MeV) on the electrical properties of CuInSe2 (CIS) thin films has been investigated. The samples were epitaxially grown on GaAs (0 0 1) substrates by Radio Frequency sputtering. As the proton fluence exceeded 1×1013 cm−2, the carrier concentration and mobility of the CIS thin films were decreased. The carrier removal rate with proton fluence was estimated to be about 1000 cm−1. The electrical properties of CIS thin films before and after irradiation were studied between 80 and 300 K. From the temperature dependence of the carrier concentration in CIS thin films, we found ND=9.5×1016 cm−3, NA=3.7×1016 cm−3 and ED=21 meV from the fitting to the experimental data on the basis of the charge balance equation. After irradiation, a defect level was created, and NT=1×1017 cm−3 for a fluence of 3×1013 cm−2, NT=5.7×1017 cm−3 for a fluence of 1×1014 cm−2 and ET=95 meV were also obtained from the same fitting. The new defect, which acted as an electron trap, was due to proton irradiation, and the defect density was increased with proton fluence.  相似文献   
90.
Both viable and non-viable orally administered Lacticaseibacillus rhamnosus CRL1505 modulate immunity in local (intestine) and distal (respiratory) mucosal sites. So, intestinal adhesion and colonization are not necessary for this probiotic strain to exert its immunomodulatory effects. In this work, a mucus-binding factor knockout CRL1505 strain (ΔmbfCRL1505) was obtained and the lack of binding ability to both intestinal epithelial cells and mucin was demonstrated in vitro. In addition, two sets of in vivo experiments in 6-week-old Balb/c mice were performed to evaluate ΔmbfCRL1505 immunomodulatory activities. (A) Orally administered ΔmbfCRL1505 prior to intraperitoneal injection of the Toll-like receptor 3 (TLR3) agonist poly(I:C) significantly reduced intraepithelial lymphocytes (CD3+NK1.1+CD8αα+) and pro-inflammatory mediators (TNF-α, IL-6 and IL-15) in the intestinal mucosa. (B) Orally administered ΔmbfCRL1505 prior to nasal stimulation with poly(I:C) significantly decreased the levels of the biochemical markers of lung tissue damage. In addition, reduced recruitment of neutrophils and levels of pro-inflammatory mediators (TNF-α, IL-6 and IL-8) as well as increased IFN-β and IFN-γ in the respiratory mucosa were observed in ΔmbfCRL1505-treated mice when compared to untreated control mice. The immunological changes induced by the ΔmbfCRL1505 strain were not different from those observed for the wild-type CRL1505 strain. Although it is generally accepted that the expression of adhesion factors is necessary for immunobiotics to induce their beneficial effects, it was demonstrated here that the mbf protein is not required for L. rhamnosus CRL1505 to exert its immunomodulatory activities in local and distal mucosal sites. These results are a step forward towards understanding the mechanisms involved in the immunomodulatory capabilities of L. rhamnosus CRL1505.  相似文献   
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