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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

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非融合内固定治疗腰椎退行性疾病的临床应用

中国组织工程研究与临床康复 2010年第22期14卷 4070-4073页

作者：刘鹏李瓦里天津中医药大学第一附属医院骨科天津市300193

背景:脊柱融合术被广泛使用于腰椎退行性疾病的治疗。经过大量的临床观察,融合后仍然存有腰部活动受限、脊柱动力学改变、邻近节段加速退变等一系列继发腰椎不稳以及椎管狭窄等症状的出现。目的:综述非融合内固定治疗腰椎退行性疾病的... 详细信息

背景:脊柱融合术被广泛使用于腰椎退行性疾病的治疗。经过大量的临床观察,融合后仍然存有腰部活动受限、脊柱动力学改变、邻近节段加速退变等一系列继发腰椎不稳以及椎管狭窄等症状的出现。目的:综述非融合内固定治疗腰椎退行性疾病的临床应用。方法:应用计算机检索1997-01/2009-12PubMed数据库(http://***/PubMed)相关文章,检索词为"lumbarspinalfusion,destabilization,non-rigidfixation",并限定文章语言种类为English。共检索到文献84篇。结果与结论:腰椎融合术仍是目前治疗腰椎不稳的标准方法,但腰椎融合率与临床满意率并不呈正比,而且腰椎融合有导致相邻节段加速退变的潜在可能。尽管目前还没有评价固定椎体间活动范围的量化标准,但理想的动态固定应能保证正常的脊柱稳定性,并且最大限度地恢复节段间的活动度。近年来,国内外已进行了大量非融合固定技术的基础和临床研究。非融合技术治疗腰椎退行性疾病是一种更符合生理需要的手术方法,可以减少一系列传统融合技术所带来的不良并发症的发生。这种方法将在新的分阶段式外科策略中扮演非常重要的角色,从而避免退变椎间节段的最终融合。

关键词：非融合内固定腰椎退行性疾病腰椎不稳综述文献

All-fiber mode converter based on superimposed long period fiber gratings

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Optoelectronics Letters 2018年第2期14卷 81-83页

作者：薛艳茹毕卫红金娃田朋飞江鹏刘强靳云 School of Information Science and Engineering Yanshan University Qinhuangdao 066004 China College of Mechanical and Electrical Engineering Hebei Normal University of Science & Technology Qinhuangdao 066004 China Key Laboratory for Special Fiber and Fiber Sensor of Heibei Province Qinhuangdao 066004 China

In this paper, a novel broadband all-fiber mode converter is proposed and experimentally demonstrated. Through writing a pair of superimposed long period fiber gratings(SLPFgs) in tow-mode fiber(TMF) with a CO_2 laser, the mode converter can realize the conversion from LP_(01) to LP_(11) owing to the phase matching condition. Numerical and experimental results show that the bandwidth of this mode converter is 3 times broader than that of a single grating converter. The converter has low loss, high coupling efficiency, small size and is easy to fabricate, so it can be widely used in mode-division multiplexing.

关键词：模式变换器纤维栅栏加长试验性小尺寸

Transient heat conduction analysis using the NURBS-enhanced scaled boundary finite element method and modified precise integration method

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Acta Mechanica Solida Sinica 2017年第5期30卷 445-464页

作者： gao Lin peng Li Jun Liu pengchong Zhang School of Hydraulic Engineering Faculty of Infrastructure EngineeringDalian University of TechnologyDalian 116024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Center for Offshore Foundation Systems Faculty of EngineeringUniversity of Western AustraliaPerth WA6009Australia

The Non-uniform rational B-spline （NURBS） enhanced scaled boundary finite element method in combination with the modified precise integration method is proposed for the transient heat conduction problems in this paper. The scaled boundary finite element method is a semi-analytical technique, which weakens the governing differential equations along the circumferential direction and solves those analytically in the radial direction. In this method, only the boundary is discretized in the finite element sense leading to a re- duction of the spatial dimension by one with no fundamental solution required. Neverthe- less, in case of the complex geometry, a huge number of elements are generally required to properly approximate the exact shape of the domain and distorted meshes are often un- avoidable in the conventional finite element approach, which leads to huge computational efforts and loss of accuracy. NURBS are the most popular mathematical tool in CAD industry due to its flexibility to fit any free-form shape. In the proposed methodology, the arbitrary curved boundary of problem domain is exactly represented with NURBS basis functions, while the straight part of the boundary is discretized by the conventional Lagrange shape functions. Both the concepts of isogeometric analysis and scaled boundary finite element method are combined to form the governing equations of transient heat conduction analy- sis and the solution is obtained using the modified precise integration method. The stiffness matrix is obtained from a standard quadratic eigenvalue problem and the mass matrix is determined from the low-frequency expansion. Finally the governing equations become a system of first-order ordinary differential equations and the time domain response is solved numerically by the modified precise integration method. The accuracy and stability of the proposed method to deal with the transient heat conduction problems are demonstrated by numerical examples.

关键词： Transient heat conduction analysisScaled boundary finite elementmethodNURBSIsogeometric analysisModified precise integration method

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基于生态足迹法的开县土地承载力研究

西南师范大学学报（自然科学版） 2011年第2期36卷 163-168页

作者：蒲鹏傅瓦利西南大学地理科学院重庆400715

本文基于生态足迹计算模型,以2003年开县生态足迹和生态承载力的计算为基础,计算并分析了开县2003—2006年的生态足迹和生态承载力,对开县的土地承载力和社会经济发展的可持续性作出了评价.从2003年的数据计算结果来看,消费和产业结构... 详细信息

本文基于生态足迹计算模型,以2003年开县生态足迹和生态承载力的计算为基础,计算并分析了开县2003—2006年的生态足迹和生态承载力,对开县的土地承载力和社会经济发展的可持续性作出了评价.从2003年的数据计算结果来看,消费和产业结构单一是造成开县生态赤字的主要原因.从时间序列上看,开县的生态足迹连续多年高于生态承载力,人均生态承载力基本保持稳定在0.426 538~0.434 438 hm2之间,但生态足迹却呈现较大的波动且与耕地的生产性土地面积的波动以及生态赤字的波动趋于一致.开县生态赤字严重,处于不可持续的发展状态,主要原因是开县经济对农业的依赖过强.

关键词：生态足迹生态承载力生态赤字可持续发展开县

Interaction between enteric epithelial cells and Peyer's patch lymphocytes in response to Shigella lipopolysaccharide: Effect on nitric oxide and IL-6 release

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World Journal of gastroenterology 2006年第24期12卷 3895-3900页

作者： Jie Chen Chuen-Pei Ng Dewi K Rowlands peng-Hui Xu Jie-Ying gao Yiu-wa Chung Hsiao-Chang Chan Epithelial Cell Biology Research Center Department of Physiology Faculty of Medicine Chinese University of Hong Kong Hong Kong China Department of Immunology Institute of Microbiology and Epidemiology Academy of Military Medical Sciences Beijing 100071 China Department of Biology Faculty of Medicine ShanxiMedical University Taiyuan 030001 Shanxi Province China

AIM： TO investigate the effect of interaction between enteric epithelial cells and lymphocytes of Peyer＇s patch on the release of nitric oxide （NO） and IL-6 in response to Shigella lipopolysaccharide （LPS）. METHODS： Human colonic epithelial cells （Caco-2） were mixed cocultured with lymphocytes of Peyer＇s patch from wild-type （C57 mice） and inducible NO synthase knockout mice, and challenged with Shigella F2a-12 LPS. Release of NO and raiL-6 was measured by griess colorimetric assay and enzyme-linked immunosorbent assay （ELISA）, respectively. RESULTS： In the absence of LPS challenge, NO was detected in the culture medium of Caco-2 epithelial cells but not in lymphocytes of Peyer＇s patch, and the NO release was further up-regulated in both cocultures with lymphocytes from either the wild-type or iNOS knockout mice, with a significantly higher level observed in the coculture with iNOS knockout lymphocytes. After Shigella F2a-12 LPS challenge for 24-h, NO production was significantly increased in both Caco-2 alone and the coculture with lymphocytes of Peyer＇s patch from the wild-type mice but not from iNOS knockout mice. LPS was found to stimulate the release of mIL-6 from lymphocytes, which was suppressed by coculture with Caco-2 epithelial cells. The LPS-induced mIL-6 production in lymphocytes from iNOS knockout mice was significantly greater than that from the wild-type mice. CONCLUSION： Lymphocytes of Peyer＇s patch maintain a constitutive basal level of NO production from the enteric epithelial cell Caco-2. LPS-induced mIL-6 release from lymphocytes of Peyer＇s patch is suppressed by the cocultured epithelial cells. While no changes are detectable in NO production in lymphocytes from both wild-type and iNOS knockout mice before and after LPS challenge, NO from lymphocytes appears to play an inhibitory role in epithelial NO release and their own mIL-6 release in response to LPS.

关键词： Shigella F2a-12 LPS Colon epithelial cells(Caco-2) Peyer's patch lymphocyte Coculture Nitricoxide Interleukin-6

Introduction to the Special Issue on Optical Coherence Tomography(OCT)

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Journal of Innovative Optical Health Sciences 2021年第1期4卷 1-2页

作者： Zhihua Ding peng Li Ruikang(Ricky)wa.g State Key Laboratory of Modern Optical Instrumentation College of Optical Science&Engineering Zhejiang University HangzhouZhejiang Province310027P.R.China Department of Bioengineering University of Washington SeattleWA 98195-5061USA

Optical Coherence Tomography(OCT)is one of the fastest developing medical imaging technologies that enables non-invasive and non-contact cross-sectional volumetric imaging by detecting the in-terference formed between... 详细信息

关键词： Optical mirror sectional

Processing technologies for gold-telluride ores

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 1-10页

作者： Jian Zhang Yao Zhang William Richmond Hai-peng wa.g Department of Metallurgical Engineering and Extractive Metallurgy Curtin University of Technology WASM Kalgoorlie WA 6430 Australia Department of Applied Chemistry Curtin University of Technology Bentley WA 6102 Australia

gold telluride ores are important gold refractory ores due to the presence of sulfides and other gangue materials. The classification and main physical properties of gold telluride ores were described, and possible treatment methods including flotation, leaching, and oxidation were reviewed. The results show that flotation procedures are much easier for gold tellurides compared to other refractory gold-bearing ores. For the conventional cyanide leaching process, pretreatment such as oxidation is required to achieve high gold recovery. Roasting is a relatively simple but not environment-friendly method; bio-oxidation technology seems to be more suitable for the oxidation of flotation concentrate. Other treatment methods involve cyanide leaching, thiourea leaching, ammoniacal thiosulfate leaching, carbon-in-pulp, and resin-in-pulp, all of which are less commonly utilized.

关键词： gold-tellurides flotation leaching oxidation

Assessment of waterlogging Risk in Lixiahe Region of Jiangsu Province Based on AVHRR and MODIS Image

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Chinese geographical Science 2008年第2期18卷 178-183页

作者： HUANg Dapeng LIU Chuang FANg Huajun peng Shunfeng Institute of geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate University of the Chinese Academy of Sciences Beijing 100049 China Huaihe River Commission Ministry of Water Resources P. R. China Bengbu 233001 China

Four images of 1991 AVHRR, 2003 and 2007 MODIS were used to extract waterlogging inundated water of three years, and three inundated water maps were overlaid to estimate waterlogging affected frequency. Based on wa-terlogging affected frequency, waterlogging hazard of pixel scale was assessed. According to the weighed score of area percentage of different waterlogging affected frequency in 13 counties/cities of Lixiahe region, waterlogging hazard rank of every county/city was assessed. waterlogging affected frequency map and 1km×1km grid landuse map were used to assess waterlogging risk of pixel scale; and then waterlogging risk rank of every county/city was assessed by the similar method by which waterlogging hazard rank of every county/city was assessed. High risk region is located mainly in core zone of Lixiahe hinterland, medium risk region is adjacent to high risk region, and low risk region is located in the most outlying area of risk zone and mainly in south to middle part of Lixiahe region. Xinghua and gaoyou belong to high risk city, Jiangyan belongs to medium risk city, and the other counties/cities have low or lower waterlogging risk. The method of assessing waterlogging risk in this paper is simple and applicable. This paper can provide guidance for the waterlogging risk analysis in broader area of Huaihe River Basin.

关键词： Lixiahe region waterlogging risk AVHRR MODIS Jiangsu Province

Molecular and cellular bases of chronic myeloid leukemia

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Protein & Cell 2010年第2期1卷 124-132页

作者： Yaoyu Chen Cong peng Dongguang Li Shaoguang Li Division of Hematology/Oncology Department of MedicineUniversity of Massachusetts Medical SchoolWorcesterMA 01605USA School of Computer and Security Science Edith Cowan UniversityMount LawleyWA 6050Australia

Chronic myeloid leukemia(CML)is a myeloproliferative disease characterized by the overproduction of granulocytes,which leads to high white blood cell counts and splenomegaly in *** on clinical symptoms and laboratory findings,CML is classified into three clinical phases,often starting with a chronic phase,progressing to an accelerated phase and ultimately ending in a terminal phase called blast *** crisis phase of CML is clinically similar to an acute leukemia;in particular,B-cell acute lymphoblastic leukemia(B-ALL)is a severe form of acute leukemia in blast crisis,and there is no effective therapy for it *** is induced by the BCR-ABL oncogene,whose gene product is a BCR-ABL tyrosine ***,inhibition of BCR-ABL kinase activity by its kinase inhibitor such as imatinib mesylate(gleevec)is a major therapeutic strategy for ***,the inability of BCR-ABL kinase inhibitors to completely kill leukemia stem cells(LSCs)indicates that these kinase inhibitors are unlikely to cure *** addition,drug resistance due to the development of BCRABL mutations occurs before and during treatment of CML with kinase inhibitors.A critical issue to resolve this problem is to fully understand the biology of LSCs,and to identify key genes that play significant roles in survival and self-renewal of *** this review,we will focus on LSCs in CML by summarizing and discussing available experimental results,including the original studies from our own laboratory.

关键词： BCR-ABL leukemic stem cells CML therapeutic agents