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41.
Time‐resolved fluorescence properties of 9‐methylanthracene (9MAn) dispersed in film of polyvinylchloride (PVC) containing carbon black were studied under tensile loadings. The fluorescence lifetime of 9MAn decreased from 5.70 to 5.55 ns, whereas the stresses acting on the films increased from 0 to 3 MPa. The change in fluorescence lifetimes of 9MAn during the stress relaxation process showed that the fluorescence lifetimes were correlated with the stresses, not with the strains. The results suggest that 9MAn is a useful probe for monitoring stresses acting on the matrix. With the use of the fluorescence properties of 9MAn, the residual tensile stresses on the skin‐layer of PVC injection‐molded test pieces were estimated. The estimated residual stresses were about ~ 1 MPa. The residual stresses were relaxed to 0 MPa with annealing at 100°C. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2600–2603, 2002 相似文献
42.
The radiation-induced copolymerization of the methyl chloride salt of N,N-dimethylaminoethyl methacrylate (DMAEM·MC) with acrylamide (AAm) was used to prepare a cationic polymer flocculant. The polymerization rate increased with increasing dose rate, polymerization temperature, monomer concentration and mole fraction of AAm in the monomer mixture. The molecular weight of the copolymer was also found to increase with monomer concentration and mole fraction of AAm, but at high concentration and fraction of AAm, intermolecular crosslinking tends to occur during the polymerization to form water-insoluble copolymer. A water-soluble copolymer having various molecular weights and cationic strengths can be synthesized by selecting suitable reaction conditions; i.e., this radiation process can provide a much higher molecular weight copolymer with a wide range of cationic strength. The flocculation effect was evaluated using sludge from wastewater of sugar manufacture. It was found that the radiation-polymerized copolymer DMAEM·MC–AAm has an excellent flocculation effect. 相似文献
43.
Deformation of poly(vinyl alcohol)–poly(sodium acrylate) composite hydrogel (PVA–PAA gel) under sinusoidally varying electric fields was studied in electrolyte solutions. The PVA–PAA gel was prepared by repeatedly freezing and thawing a mixed solution of PVA and polyacrylic acid. A cyclic bending–straightening motion of the PVA–PAA gel rods of about 1 mm in diameter have been observed in Na2CO3 aqueous solutions under the fields. The PVA–PAA gel had a response time of less than several hundreds milliseconds. The bending has also been observed in organic solvents containing an electrolyte when the organic solvent is electrolyzed. It was found that the motion of the gel under electric fields of less than 1 Hz occurred mainly through swelling due to the change of the osmotic pressure based upon the difference of the ion concentration. However, it has not been determined whether the motion at higher frequencies is caused by the osmotic effect. © 1993 John Wiley & Sons, Inc. 相似文献
44.
Keiji Mimura Susumu Yukawa Yoshio Mori Kazuya Okada Masatoshi Mune Osamu Nishikawa Akira Hibino Miyahiko Sonobe Tetuya Goto Hiroshi Nomoto 《Lipids》1991,26(12):1102-1107
We investigated the effect of platelet-activating factor (PAF) and of the PAF specific antagonist CV-6209 on plasma lipid
metabolism, and particularly on post-heparin plasma lipolytic activity in male Wistar rats. Lipoprotein lipase (LPL) activity
was enhanced by intravenous injection of PAF before intravenous injection of heparin when the PAF dose was low (0.2 μg/kg).
PAF activated hepatic triacylglycerol lipase (HTGL) activity dose-dependently. Plasma triacylglycerols (TG) significantly
decreased with the activation of LPL and/or HTGL. Plasma total cholesterol (TC) and phospholipid (PL) levels decreased at
a low dose of PAF (0.2 μg/kg), but increased when higher doses were used. The PAF antagonist CV-6209 partially reversed the
PAF induced effects on HTGL, TC and PL.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
45.
Kiyoshi Itatani Ryuji Tsukamoto Anne C. A. Delsing Hubertus T. Hintzen Isao Okada 《Journal of the American Ceramic Society》2002,85(7):1894-1896
Aluminum nitride (AlN)–silicon carbide (SiC) nanocomposite powders were prepared by the nitridation of aluminum-silicon carbide (Al4 SiC4 ) with the specific surface area of 15.5 m2 ·g−1 . The powders nitrided at and above 1400°C for 3 h contained the 2H-phases which consisted of AlN-rich and SiC-rich phases. The formation of homogeneous solid solution proceeded with increasing nitridation temperature from 1400° up to 1500°C. The specific surface area of the AlN–SiC powder nitrided at 1500°C for 3 h was 19.5 m2 ·g−1 , whereas the primary particle size (assuming spherical particles) was estimated to be ∼100 nm. 相似文献
46.
Shinsuke Nagamine Yosuke Mizuno Yuta Hikima Kiyomi Okada Long Wang Masahiro Ohshima 《应用聚合物科学杂志》2021,138(7):49851
Cellulose microfibers (CMFs) having surfaces modified with polydopamine (PDPA) and octadecylamine (ODA) were prepared, and their reinforcing abilities for polypropylene (PP) were investigated. The PDPA coating was made via self-polymerization of dopamine (P-CMF), and subsequent alkylation was conducted by the reaction with ODA (OP-CMF). The modified CMFs exhibited improved dispersibility in the PP matrix due to the reduced hydrophilicity. The OP-CMF/PP composite prepared by batch mixing had a higher tensile modulus compared to that for the pure PP and composites with unmodified CMFs. However, excess alkylation lowered the tensile modulus, and the presence of an optimal degree of alkylation was demonstrated. The CMF/PP-IM composites fabricated by injection molding exhibited improved tensile properties compared to those prepared by batch mixing. Both the tensile modulus and yield stress were increased by increasing the CMF content and improved by the surface modification of the CMFs. 相似文献
47.
本文通过测量不同金刚石粒度的高频感应钎焊金刚石砂轮磨削花岗石过程中的磨削力,对砂轮所受的法向力和切向力进行了研究。对不同粒度条件下磨削深度、进给速度和砂轮线速度对磨削力的影响进行了分析。研究发现磨削力随砂轮线速度的增大而减小,随磨削深度和进给速度的增大而增大,磨削深度对磨削力的影响程度比进给速度大。小粒度金刚石磨削时,磨削三要素对磨削力的影响比大粒度金刚石磨削时大。 相似文献
48.
Yoshiyuki Kibe Yusuke Okada Kimiyuki Mitsui 《International Journal of Machine Tools and Manufacture》2007,47(11):1728-1737
In the shearing process, clearance has a significant effect on machining accuracy. However, the relationship between uneven clearance caused by misalignment of tool position and machining accuracy remains unclear. This is attributed to the fact that, previously, the effect was small because the thickness of the workpiece was not so thin, and a method for precisely measuring and adjusting the tool position had not been established. Therefore, in the present study, a new method of adjusting the initial tool position is developed. In addition, punching experiments are conducted under the condition that the initial tool position is adjusted to an accuracy of 2 μm or better, and the effects of clearance on machining accuracy, shape of cross-section, and diameter of hole, are investigated in three types of materials. From these results, the importance of adjusting the initial tool position is clarified. 相似文献
49.
50.
Giri RR Ozaki H Okada T Takikita S Taniguchi S Takanami R 《Water science and technology》2011,64(10):1980-1986
The widespread detection of perfluorinated compounds (PFCs) in the water environment has been a concern for the last several years, while effluents from wastewater treatment facilities are the major sources of these compounds. Even advanced oxidation technologies (AOTs) are not useful for mineralization of the compounds due to their very high stability. Photochemical techniques using particularly vacuum UV (VUV) have been found to be very promising in this regard. But the use of VUV in UV-based AOTs has still not progressed much. Moreover, the impact of water quality on PFCs photomineralization is unknown. This investigation aimed to assess photomineralization potentials of perfluorooctanoic acid (PFOA) in ultrapure water (UPW), tap water (TW), surface water and treated wastewater effluent using a reactor setup enabling maximum utilization of VUV emission of low pressure lamp in laboratory batch experiments. Neya River water (NRW) and the Nakahama Wastewater Treatment Plant Effluent (NWWTPE) represented surface water and treated wastewater effluent respectively. Also, tests were carried out in 50% diluted NRW and NWWTPE. PFOA photomineralization in terms of PFOA removal, defluorination and total organic carbon (TOC) removal are discussed. The usefulness of the method for PFOA mineralization in organic-rich wastewaters, and further research needs are also highlighted. 相似文献