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材料热处理学报 2004年第5期25卷 480-485页

作者： Tsuyoshi Sugimoto youichi watanabe Nissan Motor Co. Ltd. 6-1 Daikoku-cho Tsurumi Yokohama JapanNissan Motor Co. Ltd. 6-1 Daikoku-cho Tsurumi Yokohama Japan

To minimize quenching distortion and dispersion, carburizing and quenching process conditions must be optimized; this includes the parts racking design used for quenching. We investigated some factors affecting carburized quenching distortion with an experiment using a hypoid gear having a shaft and with numerical simulation methods. The experimental results and those obtained from simulation were generally in agreement. Focusing on the surface temperature distribution in the gear, we studied quenching distortion characteristics in terms of changes in tooth profile and helix deviation. In our experiments, distortions occur during quenching in 373 K oil after austenitized temperature treatments conducted with various attitudes. We calculated the distortions by simulating the carburized oil-quenching process for the hypoid gear. Our results show large differences between the cooling rates of the tooth toe, middle section, and heel edges, and these greatly influence the change in tooth profile and helix deviation. We found that reducing the differences in temperatures on the gear surfaces during quenching is most important for minimizing the quench distortion of the hypoid gear.

关键词：淬火变形螺旋偏差外形偏差冷却曲线传热系数准双曲面齿轮

Development of High Strength Steel Designed for Carbonitriding with High Nitrogen Content to Be Used for Automatic Transmission Gears

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材料热处理学报 2004年第5期25卷 382-385页

作者： youichi watanabe Nissan Motor Co. Ltd. 6-1 Dalkoku-cho Tsurumi-ku Yokohama Japan

To downsize and lighten automatic transmission components, the gears installed must be strengthened in terms of pitting endurance and/or wear resistance. The most important metallurgical factor affecting fractures is well known to be resistance to softening when steel is tempered at approximately 573 K. Carbonitriding with a high amount of nitrogen is a very effective production technique because nitrogen increases the resistance during tempering. However, structural anomalies begin to appear in the surface layer when the nitrogen content exceeds 0.6 mass% in the chromium steel generally used. To address this, we have developed new high-strength chromium steel with an optimized chemical composition that effectively inhibits anomalies even when Carbonitriding with a nitrogen content of more than 0.6 mass%. We performed a drivetrain durability test on an automatic transmission component designed to have excellent contact fatigue strength and a tooth root bending impact and fatigue strength. We found that the developed steel that was carbonitrided with a content of about 0.9 mass%, and then shot peened hard, has a pitting life of roughly 4.5 times that of conventionally manufactured steel.

关键词：碳氮共渗传动齿轮喷丸硬化接触疲劳高强度钢

Development of New Sliver Probe for Cooling Power Test of Polymer Quenchants

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材料热处理学报 2004年第5期25卷 437-442页

作者： Michiharu NARAZAKI Mamoru TAJIMA Shigeru ASADA Katsumi ICHITANI Hideo YOKOTA Mitsugu TANAKA youichi watanabe Utsunomiya University Utsunomiya JapanKanagawa University Yokohama JapanNippon Grease Co. Ltd. Osaka JapanIdemitsu Kosan Co. Ltd. Chiba JapanNippon Oil Corporation Yokohama JapanNissho Engineering Co. Ltd. Kobe JapanNissan Motor Co. Ltd. Yokohama Japan

Working group on cooling power test of quenchants of Japanese Heat Treatment Society has studied on the new method for testing cooling power of aqueous quenchants. This method employed the cooling curve test of a new sliver rod probe, which has a metal-sheathed thermocouple at its geometrical center. The experimental study has clarified that the new silver probe has more excellent durability than the JIS silver probe employed for cooling power test of heat treating oils (JIS K 2242) and an aluminum alloy probe. Good repeatability and reproducibility of the cooling curves during polymer quenching have been confirmed. This new method is useful especially for cooling power test of aqueous quenchants used for solution heat treatment of aluminum alloys. This new silver rod probe is expected to be adopted for the revised version of JIS K 2242 as the cooling power test method for aqueous quenchants.

关键词：聚合物淬火剂动力试验冷却曲线银探测器

用于自动变速齿轮高氮势碳氮共渗高强度钢的研制

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綦齿传动 2005年第2期 16-19页

作者： youichi watanabe 胡明霞（译）赵世鑫（校） Nissan Motor Co. Ltd.6-1Daikoku-choTsurumi-kuyokohamaJapan 不详

为使自动变速零件小型化和轻量化。必须在抗点蚀和，或耐磨方面强化齿轮。影响破断的最重要的冶金因素是钢在约573K温度回火时的抗软化能力。采用高氮势进行碳氮共渗是一种非常有效的制造技术，因为氮提高抗回火性。但是，在通常使用的... 详细信息

为使自动变速零件小型化和轻量化。必须在抗点蚀和，或耐磨方面强化齿轮。影响破断的最重要的冶金因素是钢在约573K温度回火时的抗软化能力。采用高氮势进行碳氮共渗是一种非常有效的制造技术，因为氮提高抗回火性。但是，在通常使用的含Cr钢中氮含量超过0．6％时开始在表面出现异常组织。为此，我们开发研究了一种新的高强度Cr钢，即使氮含量超过0．6％，钢中最佳的化学成分可有效地阻止异常组织的出现。传动系统耐久疲劳试验表明：自动变速零件具有优良的接触疲劳强度和齿根弯曲冲击、疲劳强度；该钢在约0．9％的氮势下碳氮共渗后再喷九处理，其点蚀寿命比传统钢高约4．5倍。

关键词：碳氮共渗氮喷丸处理接触疲劳强度点蚀齿轮

用计算机模拟法对渗碳的准双曲面主动锥齿轮淬火变形的关键因素的评定

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綦齿传动 2006年第2期 15-20页

作者： Tsuyoshi Sugimoto youichi watanabe 翁远松（译）赵世鑫（校） Nissan Motor Co. Ltd.6-1Daikoku-choTsurumiYokohamaJapan 不详

为使淬火变形和偏差减至最小．渗碳和淬火工艺必须最佳化。这当中已包括零部件用于淬火的挂装设计。作者以准双曲面主动齿轮为例，用数字模拟方法对一些影响渗碳淬火变形的因素进行了研究和试验。试验结果与模拟方法获得的结果是一致的... 详细信息

为使淬火变形和偏差减至最小．渗碳和淬火工艺必须最佳化。这当中已包括零部件用于淬火的挂装设计。作者以准双曲面主动齿轮为例，用数字模拟方法对一些影响渗碳淬火变形的因素进行了研究和试验。试验结果与模拟方法获得的结果是一致的。重点是对齿轮表面温度分布的研讨，作者根据齿形的变化和螺旋线偏差研究了淬火变形特性。在试验中，以各种状态的处理温度奥氏体化后，在100℃的油中淬火时均出现变形。作者用准双曲面齿轮通过模拟渗碳油淬过程来预测变形。结果表明，在齿顶、齿中部和齿根边缘的冷却率间差异很大，而这些又很大程度上影响着齿形和螺旋线偏差的变化。作者发现在淬火期闻，降低齿轮表面的温差．对于降低准双曲面齿轮的淬火变形是极为重要的。

关键词：淬火变形螺旋线偏差齿形偏差模拟冷却曲线传热系数准双曲面齿轮

Numerical Method for Boltzmann Equation with Soroban-Grid CIP Method

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Communications in Computational Physics 2007年第4期2卷 760-782页

作者： youichi Ogata Hyo-Nam Im Takashi Yabe Department of Mechanical Sciences and Engineering Tokyo Institute of Technology2-12-1 Meguro-kuOokayama 152-8552Japan.

A new numerical scheme to solve the Boltzmann equation in phase space for rarefied gas is described on the basis of the Cubic Interpolated Propagation(CIP)*** CIP procedure is extended to adaptive unstructured grid system by the Soroban *** grid points in velocity space can move dynamically following the spread of velocity space in a spatially localized *** adaptively moving points in velocity space are similar to the particle codes but can provide higher-orderaccurate *** solutions obtained by the Soroban-grid CIP are examined and the validity is discussed.

关键词： CIP Boltzmann equation Soroban grid.

An Accurate Numerical Scheme for Maxwell Equation with CIP-Method of Characteristics

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Communications in Computational Physics 2006年第2期1卷 311-335页

作者： youichi Ogata Takashi Yabe Kouichi Odagaki Department of Mechanical Sciences and Engineering Tokyo Institute of Technology2-12-1 Meguro-kuOokayama 152-8552Japan

A new multi-dimensional scheme for the Maxwell equations is established by the CIP method in combination with the method of characteristics(CIP-MOC).In addition,the CIP-MOC can be extended to arbitrary grid system by the Soroban grid without losing the third-order *** the accuracy fixed,the grid points required for the CIP are 40 times less than the conventional schemes like the FDTD in three *** solutions obtained by the CIP-MOC are compared with analytical solution and the FDTD in plane-wave scattering by a perfectly-conducting circular cylinder,and the CIP-MOC agrees very well with analytical *** Soroban grid is also applied to the Vlasov equation that describes the kinematics of plasmas that is frequently combined with the Maxwell *** adaptively moving points in velocity space are similar to the particle codes but can provide accurate solutions.

关键词： Maxwell equation Vlasov equation CIP method method of characteristics Soroban grid

Adenocarcinoma arising from heterotopic pancreas at the third portion of the duodenum

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World Journal of Gastroenterology 2015年第13期21卷 4082-4088页

作者： Nobutada Fukino Takatsugu Oida Kenji Mimatsu youichi Kuboi Kazutoshi Kida Department of Surgery Japan Community Healthcare Organization Yokohama Central HospitalKanagawa 231-8553Japan Department of General Surgical Science Nihon University HospitalTokyo 101-8309Japan

A 62-year-old Japanese man presented to our hospital with a history of weight loss of 6 kg in 4 mo. Imaging examinations revealed a tumor located on the third portion of the duodenum with stenosis. We suspected duodenal carcinoma and performed pancreas-preserving segmental duodenectomy. Adenocarcinoma arising from a heterotopic pancreas at the third portion of the duodenum was finally diagnosed by immunohistochemical staining. Malignant transformation in the duodenum arising from a heterotopic pancreas is extremely rare; to our knowledge, only 13 cases have been reported worldwide, including the present case. The most common location of malignancy is the proximal duodenum at the first and descending portion. Herein, we describe the first case of adenocarcinoma arising from a heterotopic pancreas, which was located in the third portion of the duodenum, with a review of the literature.

关键词： Adenocarcinoma Heterotopic pancreas Duodenum Segme

Pancreatic mass as an initial manifestation of polyarteritis nodosa:A case report and review of the literature

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World Journal of Gastroenterology 2015年第3期21卷 1014-1019页

作者： Yoshihiro Yokoi Ippei Nakamura Takeshi Kaneko Tomoki Sawayanagi youichi Watahiki Makoto Kuroda Department of Surgery Shinshiro Municipal HospitalAichi 441-1387Japan Department of Internal Medicine Shinshiro Municipal HospitalAichi 441-1387Japan Department of Pathology Fujita Health UniversityAichi 470-1192Japan

Classic polyarteritis nodosa(PAN) that targets mediumsized muscular arteries and microscopic polyangiitis(MPA),characterized by inflammation of small-caliber vessels and the presence of circulating myeloperoxidase anti-neutrophil cytoplasmic antibodies(MPO-ANCA),are distinct clinicopathological entities of systemic vasculitis.A 66-year-old woman presented with fever,cholestasis and positive *** examination showed a pancreatic mass compressing the bile ***,we performed *** examination revealed that necrotizing vasculitis predominantly affecting the medium-sized vessels,spared arterioles or capillaries in the pancreas,a finding consistent with ***,renal biopsy revealed small-caliber vasculitis and glomerulonephritis,supporting *** initial manifestation of a pancreatic mass associated with vasculitis has only been reported in 7 *** diagnosis is challenging because no reliable clinico-radiological findings have been *** should be aware of such cases and early diagnosis followed by immunosuppression is *** findings may reflect a polyangiitis overlap syndrome coexisting between pancreatic PAN and renal MPA.

关键词： Classic polyarteritis nodosa Microscopic polyangii

PiggyBac transposon-mediated gene delivery efficiently generates stable transfectants derived from cultured primary human deciduous tooth dental pulp cells(HDDPCs) and HDDPC-derived iPS cells

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International Journal of Oral Science 2015年第3期7卷 144-154页

作者： Emi Inada Issei Saitoh Satoshi watanabe Reiji Aoki Hiromi Miura Masato Ohtsuka Tomoya Murakami Tadashi Sawami youichi Yamasaki Masahiro Sato Department of Pediatric Dentistry Kagoshima University Graduate School of Medical and Dental Sciences Division of Pediatric Dentistry Graduate School of Medical and Dental Science Niigata University Animal Genome Research Unit Division of Animal Science National Institute of Agrobiological Sciences Functional Biomolecules Research Group National Agriculture and Food Research Organization Division of Basic Molecular Science and Molecular Medicine School of Medicine Tokai University Section of Gene Expression Regulation Frontier Science Research Center Kagoshima University

The ability of human deciduous tooth dental pulp cells（HDDPCs） to differentiate into odontoblasts that generate mineralized tissue holds immense potential for therapeutic use in the field of tooth regenerative medicine. Realization of this potential depends on efficient and optimized protocols for the genetic manipulation of HDDPCs. In this study, we demonstrate the use of a Piggy Bac（PB）-based gene transfer system as a method for introducing nonviral transposon DNA into HDDPCs and HDDPC-derived inducible pluripotent stem cells. The transfection efficiency of the PB-based system was significantly greater than previously reported for electroporation-based transfection of plasmid DNA. Using the neomycin resistance gene as a selection marker, HDDPCs were stably transfected at a rate nearly 40-fold higher than that achieved using conventional methods. Using this system, it was also possible to introduce two constructs simultaneously into a single cell. The resulting stable transfectants, expressing td Tomato and enhanced green fluorescent protein, exhibited both red and green fluorescence. The established cell line did not lose the acquired phenotype over three months of culture. Based on our results, we concluded that PB is superior to currently available methods for introducing plasmid DNA into HDDPCs. There may be significant challenges in the direct clinical application of this method for human dental tissue engineering due to safety risks and ethical concerns. However, the high level of transfection achieved with PB may have significant advantages in basic scientific research for dental tissue engineering applications, such as functional studies of genes and proteins. Furthermore, it is a useful tool for the isolation of genetically engineered HDDPC-derived stem cells for studies in tooth regenerative medicine.

关键词： drug selection electroporation genetically modified human deciduous tooth dental pulp cells Piggy Bac