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Association between Tropical Convection and Boreal Wintertime Extratropical Circulation in 1982/83 and 1988/89

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Advances in Atmospheric Sciences 2003年第4期20卷 593-603页

作者： ja-Yeon MOON Kyung-ja HA Climate Research Laboratory Meteorological Research InstituteSeoul156-720KoreaDepartment of Atmospheric SciencesPusan National UniversityPusan609-735Korea

Boreal wintertime extratropical circulation is studied in relation to the tropical convection during the 1982/83 El Niño and 1988/89 La Niña. The anomaly structure of 1982/83 and 1988/89 over the extratropics reveals remarkably different features as the longitudinal tropical forcing region changes. The Rossby wave source (Positive) shows the largest maximum over East Asia in both years due to the persistent heating from the western Pacific warm pool area. However, the sink term shows contrasting features over the subtropics and extratropics between the two years. In the El Niño year, enhanced tropical convection over the eastern Pacific produces the Rossby wave sink at 10°N and shifted eastward over the North Pacific, while in the La Niña year, the sink area is shifted westward over the North Pacific. The contrasting features between the two events in mean-eddy interaction appears especially over the downstream area of the East Asian Jet. The extension (retraction) of the meanflow eastward (westward) to the east (west) of the dateline is related with the effect of the westward (eastward) E-vector and the strengthening (weakening) of the negative anomalies of the barotropic growth of kinetic energy. Hence, almost opposite characteristics between the two events can explain the close relationship of tropical convection and the extratropical internal variability.

关键词： tropical convection extratropical circulation rossby wave source mean-eddy interaction

Ductile Phase Toughened Brittle Materials

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Journal of Materials Science & Technology 1996年第2期12卷 124-134页

作者： Sun, XD Yeomans, ja UNIV SURREY DEPT MAT SCI & ENGNGUILDFORD GU2 5XHSURREYENGLAND

Toughening of brittle materials by the inclusion of ductile phases is governed by several important factors which include ceramic-ductile phase interfacial bond strength, physical and chemical compatibility between ceramic and ductile phase, geometry and mechanical properties of ductile phase. The present understanding of the effect of these factors on toughening is reviewed and clarified. Continuous ductile phases (network, fibre or plate) are found to be more efficient for the toughening of brittle materials than discrete ductile particles. However, ductile particle toughened brittle materials have the advantages of material homogeneity, isotropy, and particularly better high temperature properties. It has been demonstrated that the influence of interfacial bond strength is determined by the geometry of the ductile phase in the composites. For the comparatively continuous ductile phase, such as ductile network, fibre or plate, comparatively weak interfacial bond strength can promote partial debonding of the brittle matrix-ductile phase interface during crack propagation and is beneficial for toughening. For discrete particulate ductile phase toughened brittle materials, the small gauge length of the ductile phase often results in the ductile phase pull-out during crack propagation which is the main limitation to toughening. Thus strong bond strength is required to ensure the bridging of the crack by the ductile phase. The coefficient of thermal expansion (CTE) mismatch between matrix and ductile phase has also been correlated with the geometry of the ductile phase. In most of the ceramic/metal systems, the CTE of the ductile metal phase is greater than that of the ceramic matrix. In the case of ductile network, fibre or plate, the residual stress created by the CTE mismatch can contribute to toughening through its influence on the initial crack opening stress while the bridging of the crack by the ductile phase is still ensured. However, for discrete ductile parti

关键词： Brittleness

ON TRANSMISSION PROBLEM FOR KIRCHHOFF TYPE WAVE EQUATION WITH A LOCALIZED NONLINEAR DISSIPATION IN BOUNDED DOMAIN

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Acta Mathematica Scientia 2012年第3期32卷 893-906页

作者： Jeong ja Bae Department of Mathematics Dongeui UniversityPusan 614-714Korea

In this article, we consider the global existence and decay rates of solutions for the transmission problem of Kirchhoff type wave equations consisting of two physi- cally different types of materials, one component is a Kirchhoff type wave equation with nonlinear time dependent localized dissipation which is effective only on a neighborhood of certain part of the boundary, while the other is a Kirchhoff type wave equation with nonlinear memory.

关键词： Existence of solution uniform decay transmission problem Kirchhoff type wave equation boundary value problem localized dissipation

Non-invasive investigation of inflammatory bowel disease

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World Journal of Gastroenterology 2001年第4期7卷 460-465页

作者： ja Tibble IBjarnason Department of Medicine GuysKings.St Thomass Medical SchoolBessemer RoadLondon SE5 9

The assessment of inflammatory activity in intestinal disease in man can be done using a variety of different techniques. These range from the use of non-invasive acute phase inflammatory markers measured in plasma such as C reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) (both of which give an indirect assessment of disease activity) to the direct assessment of disease activity by intestinal biopsy performed during endoscopy in association with endoscopic scoring systems. Both radiology and endoscopy are conventional for the diagnosis of inflammatory bowel disease (IBD). However these techniques have severe limitations when it comes to assessing functional components of the disease such as activity and prognosis. Here we briefly review the value of two emerging intestinal function tests. Intestinal permeability, although ideally suited for diagnostic screening for small bowel Crohn's disease, appears to give reliable predictive data for imminent relapse of small bowel Crohn's disease and it can be used to assess responses to treatment. More significantly it is now clear that single stool assay of neutrophil specific proteins (calprotectin, lactoferrin) give the same quantitative data on intestinal inflammation as the 4 day faecal excretion of 111Indium labelled white cells. Faecal calprotectin is shown to be increased in over 95% of patients with IBD and correlates with clinical disease activity. It reliably differentiates between patients with IBD and irritable bowel syndrome. More importantly, at a given faecal calprotectin concentration in patients with quiescent IBD, the test has a specificity and sensitivity in excess of 85% in predicting clinical relapse of disease. This suggests that relapse of IBD is closely related to the degree of intestinal inflammation and suggests that targeted treatment at an asymptomatic stage of the disease may be indicated.

关键词： Biological Markers Feces Humans Inflammatory Bowel Diseases Intestinal Mucosa

GLOBAL EXISTENCE FOR THE NONHOMOGENEOUS QUASILINEAR WAVE EQUATION WITH A LOCALIZED WEAKLY NONLINEAR DISSIPATION IN EXTERIOR DOMAINS

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Acta Mathematica Scientia 2009年第5期29卷 1203-1215页

作者： Jeong ja Bae Department of Mathematics University of Ulsan

It is proved that the global existence for the nonhomogeneous quasilinear wave equation with a localized weakly nonlinear dissipation in exterior domains.

关键词： quasilinear wave equation localized weakly nonlinear dissipation exterior domains

On Uniform Decay for Transmission Problem of Kirchhoff Type Viscoelastic Wave Equation

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Acta Mathematica Sinica,English Series 2010年第7期26卷 1197-1206页

作者： Jeong ja BAE Department of Mathematics Dongeui University

In this paper we consider the large time behavior of solutions to an n-dimensional transmission problem for two Kirchhoff type viscoelastic wave equations, that is, the wave propagation over bodies consisting of two physically different types of materials. One component is a simple elastic part while the other is a viscoelastic component endowed with a long range memory. We show that the dissipation produced by the viscoelastic part is strong enough to produce exponential or polynomial decay of the solution

关键词： existence of solution uniform decay wave equation boundary value problem a priori estimates

不同益生菌对亚东鲑生长性能和生化指标的影响

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西南农业学报 2024年第5期37卷 1116-1123页

作者：何文佳王万良张忭忭西藏自治区农牧科学院水产科学研究所拉萨850000 西藏土著鱼类繁育与利用技术工程研究中心拉萨850000 西藏自治区渔业与种质资源利用重点实验室拉萨850000 中国水产科学研究院东海水产研究所上海200090

【目的】旨在探讨饲料中添加不同益生菌对亚东鲑(Salmo trutta)生长性能、消化酶活性和血清生化指标的影响。【方法】选择初始体质量为(84.57±1.83)g的亚东鲑鱼种630尾,随机分成7组,每组3个平行,每个平行30尾。对照组投喂基础饲料,实... 详细信息

【目的】旨在探讨饲料中添加不同益生菌对亚东鲑(Salmo trutta)生长性能、消化酶活性和血清生化指标的影响。【方法】选择初始体质量为(84.57±1.83)g的亚东鲑鱼种630尾,随机分成7组,每组3个平行,每个平行30尾。对照组投喂基础饲料,实验组分别添加不同益生菌(酵母菌、EM菌、乳酸菌、枯草芽孢杆菌、复合芽孢杆菌、地衣芽孢杆菌)至基础饲料,饲养3个月。【结果】添加不同益生菌对亚东鲑都具有促生长作用,试验组体长增长率、增重率、特定生长率、食物转化率和摄食率等指标均显著高于对照组(P0.05),而其他菌组之间均有不同程度影响。【结论】综合考虑存活率、生长特性、消化酶活性和血清生化指标,添加EM菌对亚东鲑健康养殖效果较好。

关键词：亚东鲑益生菌生长性能生化指标

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多规格转台轴承组件的自动紧钉装置

制造技术与机床 2024年第6期 183-188页

作者：王凯韩银平贾长安黄胜军西安精雕精密机械工程有限公司陕西西安710000 北京精雕科技集团有限公司北京102308

在装配转台轴承组件时,需要按照十字交叉顺序分三步拧紧固定螺钉,现有的装紧钉方式存在效率低和紧钉质量低等问题。文章设计了一种多规格转台轴承组件的自动紧钉装置,实现了多规格转台轴承组件的自动定位夹紧、装钉、按照十字交叉顺序... 详细信息

在装配转台轴承组件时,需要按照十字交叉顺序分三步拧紧固定螺钉,现有的装紧钉方式存在效率低和紧钉质量低等问题。文章设计了一种多规格转台轴承组件的自动紧钉装置,实现了多规格转台轴承组件的自动定位夹紧、装钉、按照十字交叉顺序分三步加扭力和加胶功能。实际使用表明,该设备工作可靠、效率高,紧钉质量得到很大提高。

关键词：转台轴承组件自动拧紧力矩螺钉

Nuclear Planetology:Especially Concerning the Moon and Mars

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Research in Astronomy and Astrophysics 2012年第10期12卷 1313-1380页

作者： Kyeong ja Kim Nobuyuki Hasebe Korea Institute of Geoscience and Mineral Resources Daejeon305-350 Korea Research Institute for Science and Engineering Waseda UniversityShinjukuTokyo 169-8555 Japan

To approach basic scientific questions on the origin and evolution of plan- etary bodies such as planets, their satellites and asteroids, one needs data on their chemical composition. The measurements of gamma-rays, X-rays and neutrons emit- ted from their surface materials provide information on abundances of major elements and naturally radioactive gamma-ray emitters. Neutron spectroscopy can provide sen- sitive maps of hydrogen- and carbon-containing compounds, even if buried, and can uniquely identify layers of carbon-dioxide frost. Nuclear spectroscopy, as a means of compositional analysis, has been applied via orbital and lander spacecraft to extrater- restrial planetary bodies： the Moon, Venus, Mars, Mercury and asteroids. The knowl- edge of their chemical abundances, especially concerning the Moon and Mars, has greatly increased in recent years. This paper describes the principle of nuclear spec- troscopy, nuclear planetary instruments carried on planetary missions so far, and the nature of observational results and findings of the Moon and Mars, recently obtained by nuclear spectroscopy.

关键词： nuclear planetology: planetary remote sensing -- elemental mapping --nuclear science payloads -- chemical abundance