This paper presents a simple machining method for trimming of CFRP (Carbon Fiber Reinforced Plastic) with an end mill, which can realize significantly high machining efficiency and long tool life with good surface finish. It seems that the conventional problems in the trimming process, such as delamination of trimmed edges, machining efficiency and tool wear, are caused by applying conventional milling conditions for metals without considering strong anisotropic material property of CFRP. In the proposed method, lead and helix angles of the end mill are selected appropriately so that the milling force suppresses the delamination. In order to finish the upper and lower edges on this concept, the upper and lower surfaces are machined separately at different lead angles. It is confirmed experimentally that the delamination is suppressed and tool life is extended at appropriate lead/helix angles, even when the feed rate (machining efficiency) becomes more than ten times higher than the conventional rate.

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近年、CFRPの使用量は航空機分野などで増加しているが、トリミング時のエンドミル加工の際に工具摩耗が著しいことや、加工面に欠陥か生じることなどの問題点がある。そこで本研究では、エンドミルの工具形状の変化が切削抵抗や加工面表層部損傷等に与える影響を明らかにした。

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エンドミルを用いてCFRPのトリミングを行う場合、工具摩耗、加工能率、および仕上げ面端部の剥離等が問題となる。本研究では、剥離を引き起こす切削力の方向に着目し、剥離を防ぐと同時に工具寿命を延長し、加工能率を飛躍的に向上する切削方法を提案する。本報では、エンドミルの刃先が仕上げ面端部に接するときの刃先稜線の方向、切削方向そして工具送り方向が、仕上げ面状態に与える影響について報告する。

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ジアミノマレオニトリルから出発して, 2,5-ジメチルフェニル基 (I), 2,5-ジクロロフェニル基 (II) をもつ標題のカルボン酸を経て, 14種のエステルと2種のアミドを合成し, 発芽試験を行ない植物毒性を調べたところ毒性を示さなかった. 上記2種のカルボン酸と2,5-ジメトキシフェニル基 (III) をもつカルボン酸から17種類のN-アルキルアミドを合成し, 同毒性を調べたところ, Iをもつカルボン酸のN-プロピル (n, iso), N-ブチル (n, iso, sec), N-アミル (iso) アミドが若干の植物毒性を示した. これらのN-アルキルアミドは除草試験でも水田雑草に対して若干の除草活性を示した. Iの5種のN,N-ジアルキルアミドは植物毒性を示さなかった.

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This paper presents a new algorithm to obtain the trajectory plot of the principal stress. From the result of the stress analysis by FEM (finite element method), "pseudo potential" is calculated on each node of triangular mesh. The trajectory of principal stress is obtained by drawing the contour line of the pseudo potential. By corresponding the attenuation of force to the broken line pattern of 10 stages, the magnitude and direction of the principal stress can be grasped simultaneously. Adopting LSQR method, processing time became substantially short. In addition, the calculation of the potential under source and sink conditions is also described.

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Destomycin C, a pseudo-trisaccaride antibiotic having an interglycosidic spiro-orthoester linkage, was synthesized. Stereoselective formation of orthoester linkage in the previously developed method, where glyconolactone and diol were coupled in the presence of TMSOTf, was studied using various derivatives of the diol, and achieved by the reaction of the diols having monosilyl or two different silyl groups. Anomerization of β-mannopyranoside was observed on the formation of orthoester in CH_2Cl_2 but depressed in ether. The total synthesis of destomycin C was performed in the following sequence: (1) formation of β-glycosidic linkage between D-mannopyranose and deoxystreptamine derivatives, (2) 2',3'-O-glycosylidenation of the pseudo-disaccharide with destomic acid derivative, which was derived from destomycin A, (3) inversion of configuration at C-4 of the mannopyranosyl moiety and (4) deprotection. Synthetic compound was proved to be identical with natural destomycin C by comparison of ^1H-NMR spectra at 500 MHz.

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Chemically synthesized chondrotin di-, tri-, and tetrasaccharides having 4-, 6-mono and 4, 6-disulfates were analyzed by mass spectrometry (MS). The MS analytical method for a slight amount of glycoconjugate was efficient to confirm its structure standing on the different point from NMR method. The sequences of these sulfated chondroitin oligosaccharides, especially the linkage position of the sulfate group, were confirmed by the measurement of the CID-MS/MS. Thus, the CID-MS/MS could distinguish between the 4- and 6-sulfated position on the galactosamine residue by the different fragmentation patterns from the desodiated ion of the common part, disaccharide GalNAcβ1→4G1cA, as a precursor ion. In this report, we demonstrate the possibility of the detection of the binding site of the sulfate group on some kinds of saccharides or glycoconjugates, as a result, we can make structural distinctions between sulfated linkage isomers or sulfated positional isomers using MS.

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最近提案された1次元区分的1次分数写像の真軌道生成法(Physica D, 268(2014), 100-105)を連分数変換と変形Bernoulli写像に適用し,典型的軌道と同じ性質をもつ真軌道が得られることを示す.また,連分数展開に大きな部分分母が頻繁に現れることで知られるBrillhartの3次無理数について検証を行い,我々の真軌道生成法の安全性を支持する結果が得られることを報告する.

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