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Effect of laser shock peening on combined low- and high-cycle fatigue life of casting and forging turbine blades

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Journal of Iron and Steel Research International 2018年第1期25卷 108-119页

作者： Cao Chen xiao-yong Zhang xiao-jun yan jun Ren Da-wei Huang Ming-jing Qi School of Energy and Power Engineering BeihangUniversity Beijing 100191 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191 China National Key Laboratory of Science and Technologyon Aero-Engine Aero-Thermodynamics Beijing 100191China Beijing Key Laboratory of Aero-Engine Structureand Strength Beijing 100191 China

Laser shock peening （LSP） is a novel effective surface treatment method to improve the fatigue performance of turbine blades. To study the effect of LSP on combined low- and high-cycle fatigue （CCF） life of turbine blades, the CCF tests were conducted at elevated temperatures on two types of full-scale turbine blades, which were made of K403 by casting and GH4133B by forging. Probabilistic analysis was conducted to find out the effect of LSP on fatigue life of those two kinds of blades. The results indicated that LSP extended the CCF life of both casting blades and forging blades obviously, and the effect of LSP on casting blades was more evident; besides, a threshold vibration stress existed for both casting blades and forging blades, and the CCF life tended to be extended by LSP only when the vibration stress was below the threshold vibra- tion stress. Further study of fractography was also conducted, indicating that due to the presence of compressive residual stress and refined grains induced by LSP, the crack initiation sources in LSP blades were obviously less, and the life of LSP blades was also longer; since the compressive residual stress was released by plastic deformation, LSP had no effect or adverse effect on CCF life of blade when the vibration stress of blade was above the threshold vibration stress.

关键词： Laser shock peening Combined low-and high-cycle fatigue life (CCF) Full-scale turbine blade S-N curve -Threshold vibration stress

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基于溯源图的网络攻击调查研究综述

电子学报 2024年第7期52卷 2529-2556页

作者：仇晶陈荣融朱浩瑾肖岩军殷丽华田志宏广州大学网络空间安全学院广东广州510555 鹏城实验室广东深圳518000 上海交通大学计算机科学与工程系上海200240 绿盟科技集团股份有限公司北京100089

网络攻击调查是实现主动防御、溯源反制的重要手段.面向高隐蔽、强对抗的现代网络攻击,研究高效率、自动化攻击调查方法,提升己方快速响应复杂网络攻击能力,是智能网络攻防关键技术之一.现有研究通过将系统审计日志建模成可表达攻击事... 详细信息

网络攻击调查是实现主动防御、溯源反制的重要手段.面向高隐蔽、强对抗的现代网络攻击,研究高效率、自动化攻击调查方法,提升己方快速响应复杂网络攻击能力,是智能网络攻防关键技术之一.现有研究通过将系统审计日志建模成可表达攻击事件因果依赖关系的溯源图,利用溯源图强大的关联分析和语义表达能力,对复杂隐蔽网络攻击进行调查,相较传统方法效果提升显著.在全面收集分析基于溯源图的攻击调查研究工作的基础上,根据溯源图利用方式及特征挖掘维度的差异,将基于溯源图的攻击调查方法划分为基于因果分析、基于深度表示学习和基于异常检测三类,总结凝练每类方法具体工作流程和通用框架.梳理溯源图优化方法,剖析相关技术从理论向产业落地的能力演变历程.归纳攻击调查常用数据集,对比分析基于溯源图的攻击调查代表性技术和性能指标,最后展望了该领域未来发展方向.

关键词：攻击调查溯源图高级持续性威胁深度学习异常检测

A novel way to synthesize Pb nanotapes in liquid ammonia

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Chinese Chemical Letters 2011年第8期22卷 993-996页

作者： Lei Sun Meng Lei Zhang xiao jun Tao yan Bao Zhao Key Laboratory for Special Functional Materials of Ministry of Education Henan University Kaifeng 475004 China

Lead nanotapes were synthesized in liquid ammonia solvent in the presence of sodium metal at low *** process was template *** electron microscopy（TEM） observations and X-ray diffraction（XRD） characterizations revealed that the as-prepared Pb nanotapes have average diameters in the range of 40-50 *** lengths up to several hundred nanometers, and exhibit cubic crystal structures.

关键词： Pb Nanotapes Chemical synthesis Liquid ammonia

Detection of H pylori antibody profile in serum by protein array

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World Journal of Gastroenterology 2006年第25期12卷 4044-4048页

作者： Feng-Chan Han Xu-jun Li Hong Jiang Li-Peng Qin Ding Li yan-Hai Guo Zhi-Guang Liu Li Zhang xiao-jun yan Institute of Genetic Diagnosis State Key Laboratory of Cancer Biology The Fourth Military Medical University Xi'an 710032 Shaanxi Province China Department of Gastroenterology Xi'an Central Hospital Xi'an 710032 Shaanxi Province China

AIM： To detect multiple H pylori antibodies in serum samples of individuals who carryHpylori by protein array. METHODS： Recombinant H pylori antigens, urease B subunit （UreB）, vacuolating toxin A （VacA） and cytotoxin associated gene A protein （CagA）, were prepared and immobilized in matrixes on nitrocellulose membrane by robotics to bind the specific immunoglobulin G （IgG） antibodies in serum. Staphylococcus protein A （SPA） labeled by colloid gold was used to integrate the immuno-complex and gave red color signal. The scanner based on charge-coupled device （CCD） could collect the image signal and convert it into digital signal. RESULTS： When human IgG was printed on the membrane in increasing concentrations and incubated with immunogold, a linear dose response curve was obtained and the detection limit for IgG was about 0.025 ng. The cutoff values, which were defined as the mean grey level plus 3 times of standard deviation, were 27.183, 28.546 and 27.402, for anti-UreB IgG, anti- CagA IgG and anti-VacA IgG, respectively, as 400 human serum samples with negative H pylori antibodies were detected by the protein array. When 180 serum samples from patients in hospital were employed for detection of IgG against UreB, CagA and VacA, the sensitivity of the protein array was 93.4%, 95.4%, 96.0%, and the specificity was 94.8%, 94.4% and 97.5%, respectively, as compared with the results obtained by ELISA. The assay also showed high reproducibility, uniformity and stability, and the results were available within 30 min. CONCLUSION： The protein array is a very practical method for rapid detection of multiple antibodies in serum samples. It is especially useful for large scale epidemiological investigation of the infection of Hpylori.

关键词： Helicobacter pylori Protein array Antibody Immunogold

Shear-thinning Catechol-modified Chitosan Hydrogel Loaded with Silver Nanoparticles for Endoscopic Submucosal Dissection

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Chinese Journal of Polymer Science 2024年第8期42卷 1147-1155页

作者： Wen-jun Feng yan-He Wu xiao-yang Liu Zheng-Ke Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

Shear-thinning hydrogels have emerged for endoscopic submucosal dissection,while wound intervention after surgery has rarely been ***,a catechol-modified chitosa n hydrogel with shear-thinning property was developed for simultaneously facilitating endoscopic submucosal dissection and postoperative wound *** from the shear-thinning and self-healing characteristics,the asprepared hydrogel showed easily endoscopic *** also performed very well as submucosal cushion,which could remain above 70%after injection for 120 min in ex vivo porcine large intestine *** fact,the cushion height of normal saline dramatically decreased to 46%of the initial height at 30 *** nanoparticles encapsulated into the network endowed the hydrogel with almost reached 100%antibacterial effect against *** and *** hemolysis ratio of the hydrogel was calculated to be as low as 0.8%.Combined with good hemocompatibility and cytocompatibility,the as-prepared hydrogel displayed much higher in vivo wound closu re and healing efficacy than normal *** results demonstrated the superiority of the shear-thinning chitosan hydrogel in facilitating clinical endoscopic submucosal dissection surgery.

关键词： Shear-thinning hydrogel Endoscopic mucosal dissection Wound healing Catechol-modified chitosan Silver nanoparticles

On the Monge–Kantorovich Mass Transfer Problem in Higher Dimensions

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1989-2004页

作者： xiao jun LU School of Mathematics Southeast UniversityNanjing 210096P.R.China

This paper mainly investigates the approximation of a global maximizer of the Monge–Kantorovich mass transfer problem in higher dimensions through the approach of nonlinear partial differential equations with Dirichlet *** an approximation mechanism,the primal maximization problem can be transformed into a sequence of minimization *** applying the systematic canonical duality theory,one is able to derive a sequence of analytic solutions for the minimization *** the final analysis,the convergence of the sequence to an analytical global maximizer of the primal Monge–Kantorovich problem will be demonstrated.

关键词： Monge-Kantorovich mass transfer singular variational problem canonical duality theory

Artemsieverolactones A—H,Eight Guaiane-Type Sesquiterpenoid Trimers from Artemisia sieversiana

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Chinese Journal of Chemistry 2024年第10期42卷 1084-1092页

作者： Wei Dong xiao-yan Huang Tian-Ze Li yan-Mei Weng Chang-An Geng Ji-jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academyof Sciences Beijing 100049China

Eight new guaiane-type sesquiterpenoid trimers,artemsieverolactones A—H,possessing unprecedented scaffolds via biocatalyzed[4+2]Diels−Alder cycloaddition reactions were identified from Artemisia *** structures were determined by comprehensive spectroscopic data,single-crystal X-ray diffraction analyses,and ECD *** terms of structure,artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane-type sesquiterpenoid through four different[4+2]Diels−Alder cycloaddition *** fibrosis assay suggested that five compounds exhibited activity against HSC-LX2 with IC_(50)values ranging from 37.8 to 117.1μmol/*** most active artemsieverolactone B(2)displayed significant inhibitory activity against HSC-LX2 with IC_(50)value of 37.8μmol/L,which was 3 times more active than the positive drug silybin(IC_(50),139.7μmol/L).Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen typeⅠ(ColⅠ),human hyaluronic acid(HA),and human laminin(HL)with IC_(50)values of 40.4μmol/L(Col I),55.1μmol/L(HL),47.3μmol/L(HA),which was 2 to 3-fold more potent than silybin.

关键词： Artemisia sieversiana Artemsieverolactones A-H Guaiane-type sesquiterpenoid trimers Antihepatic fibrosis Extracellular matrix Cancer NMR spectroscopy X-ray diffraction

Modified conditioning regimen busulfan-cyclophosphamide followed by allogeneic stem cell transplantation in patients with multiple myeloma

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Chinese Medical Journal 2007年第6期120卷 463-468页

作者： ZHANG xiao-hui HUANG xiao-jun LIU Kai-yan XU Lan-ping LIU Dai-hong CHEN Huan CHEN Yu-hong WANG Jing-zhi HAN Wei LU Dao-pei Institute of Hematology Peking University People＇s Hospital Beijing 100044 China

Background Allogeneic stem cell transplantation is a potential curative approach in patients with multiple myeloma. The very high transplant related mortality associated with standard allogeneic stem cell transplantation is currently the major limitation to wider use of this potentially curative treatment modality. The challenge for clinical investigators is to reduce the incidence of post-transplant complications for patients receiving autologous hematopoietic stem cell transplantion for multiple myeloma. In this study the toxicity and efficacy of modified myeloablative conditioning regimen followed by allogeneic stem cell transplantation was investigated in patients with multiple myeloma. Methods The conditioning regimen consisted of hydroxyurea, cytarabine, busulfan, cyclophosphamide, and semustine. Ten patients underwent allogeneic transplantation among them hydroxyurea （40 mg/kg） was administered twice on day -10 and cytarabine （2 g/ms） was given on day -9, busulfan was administered orally in four divided doses daily for 3 days （days -8 to -6）. The dose of busulfan was 12 mg/kg in the protocol followed by cyclophosphamide intravenously over 1 hour on days -5 and -4 （1.8 g/m^2）, and with semustine （Me-CCNU） 250 mg/m^2 on day -3. Results Chimerism data were available on all patients and all patients achieved full donor chimerism without graft failure. Six patients had not acute graft-versus-host disease （GVHD, 36.4%; 95% CI： 13.9%-38.6%）. Two patients （18.2%） developed grade Ⅰ acute GVHD （95% CI： 10.9%-35.9%） and grade Ⅱ acute GVHD occurred in one patient （9.1%; 95% Cl. 8.4%-32.3%）. Severe grade IVa GVHD was seen in one patient, who died from acute GVHD. The incidence of chronic GVHD was 22.2% （95% Cl： 11.7%-36.7%）, among them one died of severe grade IV GVHD and one developed multiorgan failure on day ＋170; the treatment-related mortality was 22.0% （95% Cl： 10.3%-34.1%）. The overall 4-year survival rate was 67.8% （95% Cl： 16.3%-46.7%）. The estimated 4-year progr

关键词： multiple myeloma stem cell transplantation modified conditioning regimen

EPC装配式高层房建项目全专业穿插施工关键技术分析

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建筑技术开发 2024年第6期51卷 27-29页

作者：迟骋丁雅鑫彭鹏罗成志林畅宇肖君彦中建二局第一建筑工程有限公司北京100176

分析梅溪湖某项目在EPC模式下穿插施工的关键技术应用。EPC(工程、采购、建造)模式通过整合设计、采购、施工及测试阶段,为项目实施提供了较全面的管理策略。首先概述项目的基本情况,包括其结构、规模和关键时间节点,然后探讨EPC合同结... 详细信息

分析梅溪湖某项目在EPC模式下穿插施工的关键技术应用。EPC(工程、采购、建造)模式通过整合设计、采购、施工及测试阶段,为项目实施提供了较全面的管理策略。首先概述项目的基本情况,包括其结构、规模和关键时间节点,然后探讨EPC合同结构、管理流程以及项目风险管理和质量控制策略。通过对梅溪湖某项目实施过程的深入分析,总结了穿插施工法的成功经验,并提出了面临的主要问题与挑战。最后,针对项目管理提出一系列的建议,以期为未来类似项目的规划与执行提供参考。

关键词： EPC模式穿插施工项目管理风险管理