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复合材料学报 2007年第3期24卷 186-192页

作者：罗冬梅汪文学高雄善裕佛山科学技术学院环境与土木工程建筑学院九州大学应用力学研究所

利用具有精确周期性边界条件的均质化理论,用宏微观有限元法分析了非连续碳纳米管呈规则和交错2种排列情况下,纳米管沿管长方向的应力分布规律。为保证传统的连续力学理论的适用性,本文中的碳纳米管采用了用分子动力学方法简化的等效纤... 详细信息

利用具有精确周期性边界条件的均质化理论,用宏微观有限元法分析了非连续碳纳米管呈规则和交错2种排列情况下,纳米管沿管长方向的应力分布规律。为保证传统的连续力学理论的适用性,本文中的碳纳米管采用了用分子动力学方法简化的等效纤维模型。规则排列所得结果与应用Cox剪滞理论及Lauke、Fu等经典理论得出的结果比较发现:除了经典理论中指出的碳纳米管长径比及纳米管体积含量2个因素外,纳米管形状及在基体中的排列方式对材料的力学性质也有较大影响。交错排列的纳米管在复合材料中有较高效率的应力转化和传递能力,碳纳米管的端部间距(2Tf)对应力的分布有较大的影响。结果显示出碳纳米管作为材料增强相的特殊性,证明了均质化理论分析碳纳米管增强复合材料应力分布规律的可行性。

关键词：碳纳米管增强复合材料均质化理论应力分布规则排列与交错排列

深海钛合金压力容器在静水压力作用下的弹塑性分析

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船舶力学 2009年第4期13卷 603-608页

作者：罗冬梅汪文学高雄善裕佛山科学技术学院环境与土木建筑学院广东佛山528000 九州大学应用力学研究所

利用*** Mentat 2005通用有限元软件对深海探测用压力容器受静水压力作用时的弹塑性失稳问题进行了计算与分析,弹性失稳数值计算的结果与用现有规范计算公式所得结果一致,均大于塑性失稳数值分析时的临界载荷。由此得出结论,对于厚壁且... 详细信息

利用*** Mentat 2005通用有限元软件对深海探测用压力容器受静水压力作用时的弹塑性失稳问题进行了计算与分析,弹性失稳数值计算的结果与用现有规范计算公式所得结果一致,均大于塑性失稳数值分析时的临界载荷。由此得出结论,对于厚壁且形状复杂的压力容器的失稳计算,用理论公式或仅用厚壳单元的弹性失稳分析是不够的,应该用3维立体单元的弹塑性失稳计算才能给出比较精确的强度预测。*** Mentat2005强大的计算和仿真功能有效地模拟了深海精密探测容器受静水压力作用时的弹塑性失稳问题,为深海精密探测容器在材料、外观等方面做进一步的设计改进提供了可靠的工具。

关键词：深海压力容器弹塑性失稳数值分析 MSC.Marc Mentat 2005

确定均质化法中精确周期性边界条件的新解法及其在复合材料刚度预测中的应用

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机械强度 2006年第4期28卷 517-523页

作者：罗冬梅汪文学高雄善裕柿本浩一佛山科学技术学院环境与建筑学院佛山528000 九州大学应用力学研究所

通过引进新的特征函数,提出一种新的求解方法,将均质化法中计算特征函数的非奇次积分方程转化为奇次积分方程,得到具有精确的周期性边界条件的均质化方法。利用该方法预测孔洞材料、短纤维增强复合材料刚度的变化,所得结果与用经典方法... 详细信息

通过引进新的特征函数,提出一种新的求解方法,将均质化法中计算特征函数的非奇次积分方程转化为奇次积分方程,得到具有精确的周期性边界条件的均质化方法。利用该方法预测孔洞材料、短纤维增强复合材料刚度的变化,所得结果与用经典方法得到的结果进行比较,验证该方法的可靠性。对于短纤维增强复合材料,分析纤维排列方式对刚度的影响,这是经典的Halpin-Tsai法和Mori-Tanaka法无法预测的,因而文中的方法具有更高的精确度和更广的适应性。

关键词：均质化法精确周期性边界条件纤维增强复合材料刚度

波形碳纳米管增强复合材料的有效刚度和局部应力的宏微观均质化数值模拟

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机械强度 2009年第4期31卷 670-674页

作者：周应龙罗冬梅汪文学高雄善裕佛山科学技术学院机电工程系佛山科学技术学院土木工程与建筑学系日本九州大学应用力学研究所九州大学

采用分子动力学方法简化的碳纳米管等效纤维模型,利用具有精确周期性边界条件的均质化理论和宏微观均质化法分析正弦波形非连续碳纳米管的有效刚度和局部应力分布规律。结果表明,纳米增强复合材料的有效刚度和局部应力对碳纳米管的波形... 详细信息

采用分子动力学方法简化的碳纳米管等效纤维模型,利用具有精确周期性边界条件的均质化理论和宏微观均质化法分析正弦波形非连续碳纳米管的有效刚度和局部应力分布规律。结果表明,纳米增强复合材料的有效刚度和局部应力对碳纳米管的波形非常敏感,碳纳米管稍有弯曲就会导致复合材料有效刚度降低和应力传递能力的下降,为揭示复合材料中碳纳米管的增强机制和改善增强效果提供理论依据。

关键词：碳纳米管增强复合材料均质化法局部应力分布

深海无人探测外压容器的优化设计及稳定性分析

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船舶工程 2008年第5期30卷 58-61,49页

作者：罗冬梅周应龙汪文学高雄善裕广东省佛山科学技术学院佛山528000 日本九州大学应用力学研究所福冈816-8580

利用有限元方法系统分析日本钛制万米深海无人探测容器(Shinkai)的外形及材料优化,计算了弹性与塑性情况容器失稳时的临界应力.结果表明容器加强肋的微小变化以及复合材料铺层方式的改变可使由钛-复合材料(CFRP)组成的三明治式压力容器... 详细信息

利用有限元方法系统分析日本钛制万米深海无人探测容器(Shinkai)的外形及材料优化,计算了弹性与塑性情况容器失稳时的临界应力.结果表明容器加强肋的微小变化以及复合材料铺层方式的改变可使由钛-复合材料(CFRP)组成的三明治式压力容器比全钛合金制压力容器的比强度增加22.5%,容器的破坏主要由塑性失稳控制.

关键词：深海外压容器无人探测优化设计失稳特征

Transfer of electrons on scratched iron surfaces:Photoelectron emission and X-ray photoelectron spectroscopy studies

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Friction 2018年第1期6卷 98-115页

作者： yoshihiro MOMOSE Daisuke SUZUKI Keika TSURUYA takao SAKURAI Keiji NAKAYAMA Department of Materials Science Ibaraki University Ashikaga Institute of Technology Institute of Mesotechnology

We report the activation energy, ΔEa, for the quantum yield in thermally assisted photoelectron emission(TAPE) under 210-nm-wavelength light irradiation, and the associated X-ray photoelectron spectroscopy(XPS) results. Samples were cleaned only in acetone and scratched in air, water, methanol, ethanol, acetone, benzene, and cyclohexane. Glow curves, describing the temperature dependence of photoelectron emission(PE) quantum yield(emitted electrons/photon), Y, were obtained. A simple method of determining ΔEa using Y, called YGC, at seven temperatures up to 353 °C, for the same Y glow curve, was proposed. The ΔEa obtained using this method was almost the same as that obtained from Y for seven stationary temperatures(YST). For scratched samples, the TAPE was measured over two cycles of temperature increase and subsequent decrease(Up1, Down1 and Up2, Down2 scans) in the 25–339 °C range, and ΔE_a was obtained from YGC. The Arrhenius plot was approximated by a straight line, although a convex swelling peak appeared in the Up1 scan. ΔE_(aUp1) was in the 0.212–0.035 eV range, depending on the environment in which scratching was performed; ΔE_(aUp1) for water was much higher than that for acetone. This was explained in terms of the mode of the acid–base interaction between the liquid molecules and the hydroxyl group of Fe–OH. The values of ΔE_(aDown1), ΔEa Up2, and ΔE_(aDown2) were in the 0.038–0.012 eV range. The total count of electrons emitted during the Up1 and Up2 scans was found to decrease with increasing ΔE_(aUp1) and ΔE_(aUp2), respectively. ΔE_(aUp2) was found to increase with increasing presence of the FeO component in the analyzed Fe oxides. The convex swelling peak was attributed to the removal of carbon materials from the scratched surface and the effect of the increased electron density of the surface hydroxyl group of FeOH under the light irradiation.

关键词： thermally assisted photoelectron emission XPS real iron scratch-inducing environment Arrhenius activation energy environment molecule-surface hydroxyl group interaction

How to maintain nutritional status after esophagectomy via the Tanaka method

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 785-793页

作者： yoshihiro Tanaka Yuta Sato Tomonari Suetsugu Junichi Mase Ritsuki Takaha Naoki Okumura Nobuhisa Matsuhashi takao Takahashi Kazuhiro Yoshida Department of Surgical Oncology Graduate School of MedicineGifu UniversityGifu 501-1194Japan.

Aim:Many therapeutic means have emerged to treat esophageal *** relating to nutritional status such as body weight maintenance are important to the continuation of these *** this study,we investigated methods to extend the administration of diversified treatments for patients with esophageal cancer,especially regarding measures to suppress body weight loss after ***:We retrospectively evaluated a strategy for preventing postoperative body weight loss which can hinder the continuation of treatment via a reconstruction method aimed at safety and comfort combined with postoperative dietary intake and nutritional support for esophageal cancer ***:The subjects comprised 386 patients who underwent subtotal stomach reconstruction during esophageal cancer surgery performed from January 2008 to January 2021 at Gifu University *** anastomotic leakage rate was 0.5%.By administering oral nutritional supplementation under strict rules using ENSURE®H during the perioperative period,the percentage of body weight loss after 5 years could be limited to 4.78%compared to that before *** assessing early feeling of fullness measured using the EORTC QLQ-OES18 at postoperative months 3,12,24,36,48,and 60 were 1.7±0.3,2.0±0.2,1.2±0.3,1.3±0.2,1.5±0.2,and 1.4±0.1,***:Considering methods to eliminate the factors that prevent continuation of treatment may lead to sustainable treatment against esophageal *** surgical reconstruction and nutritional management will allow maintenance of body weight and good quality of life.

关键词： Esophageal cancer nutrition reconstruction oral nutritional supplementation

Clinical outcomes of Clutch Cutter endoscopic submucosal dissection for older patients with early gastric cancer

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World Journal of Gastrointestinal Oncology 2017年第10期9卷 416-422页

作者： yoshihiro Otsuka Kazuya Akahoshi Kayoko Yasunaga Masaru Kubokawa Junya Gibo Shigeki Osada Kayo Tokumaru Kazuaki Miyamoto takao Sato Yuki Shiratsuchi Masafumi Oya Hidenobu Koga Eikichi Ihara Kazuhiko Nakamura Department of Gastroenterology Aso Iizuka Hospital Diagnosis Procedure Combination Coding Management Office Aso Iizuka Hospital Department of Pathology Aso Iizuka Hospital Clinical Research Supportive Office Aso Iizuka Hospital Department of Medicine and Bioregulatory Science Graduate School of Medical SciencesKyushu University

AIM To evaluate the clinical outcome of endoscopic submucosal dissection using the Clutch Cutter(ESDCC) in older patients. METHODS We reviewed 232 consecutive patients with early gastric cancer who underwent ESDCC between June 2010 and February 2014 at Aso Iizuka Hospital. We divided patients into two groups according to age: Older patients(> 80 years, n = 64) and non-older patients(≤ 80 years, n = 168). We retrospectively compared the prevalence rates of pre-existing comorbidities, anticoagulant therapy, en bloc resection, mean duration of hospitalization, incidence of ESDCC-related complications, change in performance status(PS) before and after ESDCC, and financial cost of admission. RESULTS The older group comprised 64 patients with a mean age of 84.1 years, and the non-older group comprised 168 patients with a mean age of 69.5 years. Older patients had significantly more pre-existing comorbidities than did non-older patients, specifically heart disease(P < 0.05). The en bloc resection rate in non-older patients was significantly higher than that in older patients(100% vs 95.3%, P = 0.02). There were no significant differences between the older and non-older groups in the incidence of ESDCC-related complications(i.e., postoperative bleeding and perforation) and the post-ESDCC change in PS. There were also no significant differences between the older and non-older groups in the mean duration of hospitalization(11.4 and 10.7 d, respectively) and financial cost of admission(657040 JPY and 574890 JPY, respectively).CONCLUSION ESDCC has a good clinical outcome in older patients.

关键词： Older patients Clutch Cutter Endoscopic submucosal dissection Early gastric cancer Financial cost Duration of hospitalization

NF-κB and ERK-signaling pathways contribute to the gene expression induced by cag PAI-positive-Helicobacter pylori infection

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World Journal of Gastroenterology 2005年第39期11卷 6134-6143页

作者： Wataru Shibata yoshihiro Hirata Haruhiko Yoshida Motoyuki Otsuka Yujin Hoshida Keiji Ogura Shin Maeda Tomoya Ohmae Ayako Yanai Yuzo Mitsuno Naohiko Seki takao Kawabe Masao Omata Department of Gastroenterology Graduate School of Medicine University of TokyoJapan Department of Functional Genomics Graduate School of Medicine University of ChibaJapan

AIM： To elucidate the sequential gene expression profile in AGS cells co-cultured with wild-type Helicobacter pylori （H pylon） as a model of Hpylori-infected gastric epithelium, and to further examine the contribution of cag-pathogenicity islands （cagPAI）-coding type IV secretion system and the two pathways, nuclear factor kappa B （NF-κB） and extracellular signal-regulated kinases （ERK） on wild-type Hpylori-induced gene expression. METHODS： Gene expression profiles induced by Hpylori were evaluated in AGS gastric epithelial cells using cDNA microarray, which were present in the 4600 independent clones picked up from the human gastric tissue. We also analyzed the contribution of NF-κB and ERK signaling on H pylori-induced gene expression by using inhibitors of specific signal pathways. The isogenic mutant with disrupted cagE （△cagE） was used to elucidate the role of cagPAI-encoding type IV secretion system in the gene expression profile. RESULTS： According to the expression profile, the genes were classified into four clusters. Among them, the clusters characterized by continuous upregulation were most conspicuous, and it contained many signal transducer activity-associated genes. The role of cagPAI on cultured cells was also investigated using isogenic mutant cagE, which carries non-functional cagPAI. Then the upregulation of more than 80% of the induced genes （476/566） was found to depend on cagPAI. Signal transducer pathway through NF-κB or ERK are the major pathways which are known to be activated by cagPAI-positive H pylori. The role of these pathways in the whole signal activation by cagPAI-positive H pyloriwas analyzed. The specific inhibitors against NF-κB or ERK pathway blocked the activation of gene expression in 65% （367/566） or 76% （429/566） of the genes whose activation appealed to depend on cagPAI. CONCLUSION： These results suggest that more than half of the genes induced by cayPAI-positive H pylori depend on NF-κB and ERK signaling activation, and thes

关键词： Helicobacter pylort, Cag-pathogenicity islands cDNA microarray, Cluster analysis Signal transduction