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Journal of Rare Earths 2009年第3期27卷 520-524页

作者：罗建军 de Rango P Fruchart d 梅金娜胡锐李金山周廉 state Key Laboratory of solidification Processing Northwestern Polytechnic University Matière Condensée Matériaux et Fonctions (MCMF) Institut NéelCNRSBP 16638042 Grenoble Cedex 9France Matière Condensée Matériaux et Fonctions(MCMF) Institut NéelCNRSBP 16638042 Grenoble Cedex 9France Consortium de Recherches Pour l'Emergence de Technologies Avancées(CRETA) CNRSBP 16638042 Grenoble Cedex 9France

Hydrogen absorption and desorption characteristics for high coercivity NddyFeCoNbCuB sintered bulk magnets were studied, by differential scanning calorimetry （dsC） measurement and hydrogenation kinetics measurement. The dsC measurements showed that hydrogenation of Nd-rich phase occurred in the temperature range of 40-185 ℃, hydrogenation of the tetragonal （Ф） phase in the temperature range of 185-220 ℃, as well as the disproportionation of the Ф phase that occurred in a broad temperature range from around 500 to 800 ℃. The hydrogenation kinetics measurements indicated that hydrogen absorption of the bulk magnets at 50 ℃ absorbed more hydrogen than at 150 ℃, although this procedure was slower at 50 ℃ than at 150℃. This phenomenon was discussed by means of pressure-concentration-temperature （p-c-T） diagrams.

关键词： hydrogen absorption hydrogen desorption sintered NddyFeCoNbCuB magnets rare earths

Experimental and Numerical Evaluation of the Performance of supersonic Two-stage High-Velocity Oxy-Fuel Thermal spray (Warm spray) Gun

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Journal of Thermal science 2011年第1期20卷 88-92页

作者： H.Katanoda H.Morita M.Komatsu s.Kuroda department of Mechanical Engineering Kagoshima University1-21-40 KorimotoKagoshima 890-0065Japan Hybrid Materials Center National Institute for Materials Science1-2-1SengenTsukubaIbaraki 305-0047Japan

The water-cooled supersonic two-stage high-velocity oxy-fuel (HVOF) thermal spray gun was developed to make a coating of temperature-sensitive material,such as titanium,on a *** gun has a combustion chamber (CC) followed by a mixing chamber (MC),in which the combustion gas is mixed with the nitrogen gas at room *** mixed gas is accelerated to supersonic speed through a converging-diverging (C-d) nozzle followed by a straight passage called the *** paper proposes an experimental procedure to estimate the cooling rate of CC,MC and barrel ***,the mathematical model is presented to predict the pressure and temperature in the MC for the specific mass flow rates of fuel,oxygen and nitrogen by assuming chemical equilibrium with water-cooling in the CC and MC,and frozen flow with constant specific heat from stagnant condition to the throat in the CC and ***,the present mathematical model was validated by comparing the calculated and measured stagnant pressures of the CC of the two-stage HVOF gun.

关键词： supersonic flow Two-stage HVOF thermal spray gun Warm spray

development of Low Carbon Microalloyed High strength Ultra-Thin Cast strip Products Produced by the Castrip~ Process With Excellent strength-ductility Properties

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Journal of Iron and steel Research International 2011年第S1期18卷 846-850页

作者： C.R. Killmore K.R. Carpenter H.R. Kaul d.G. Edelman J.M. Cairney s.P. Ringer J.G. Williams P.C. Campbell W.N. Blejde Bluescope steel Five Islands Road Pt Kembla 2500 Australia Nucor steel Indiana 4537 s. Nucor Rd. Crawfordsville IN 47933 USA Australian Centre for Microscopy and Microanalysis University of Sydney NSW 2006 Australia Castrip LLC1915 Rexford Rd. Charlotte NC 28211 USA

The CAsTRIP* process produces a range of high strength Ultra-thin Cast strip (UCs) products (380-550 MPa) in thicknesses between 0.9 mm and 1.5 mm, which is very challenging to produce via conventional hot and cold rolled processing routes. The twin roll CAsTRIP process fully exploits the hardenability and strengthening potential of Nb in a low C-Mn-Nb-V microalloyed steel type. significant microstructural strengthening from solute Nb was obtained, even at low microalloying levels, as well as modest Mn additions, through enhancing the hardenability and further strengthening was obtained in coated products by exploiting age hardening during processing on a continuous hot dip galvanising line. Atom probe tomography and TEM determined that Nb was retained in solid solution and subsequent age hardening resulted from the formation of Nb and V rich nanosized particles. Age hardening was achieved without loss of ductility producing galvanised strip with an excellent strength-ductility combination (Y.s. >600 MPa, T.E. >10%).

关键词： strip casting microalloying niobium ntom probe tomography age hardening high strength CAsTRIP Process

denitrification Rates and Their Controlling Factors in streams of the Han River Basin with different Land-Use Patterns

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Pedosphere 2014年第4期24卷 516-528页

作者： s.P.JUNG Y.J.KIM H.KANG school of Civil and Environmental Engineering Yonsei UniversitySeoul 120-749(Korea) River and Coastal Research division Korea Institute of Construction TechnologyGoyang 211-712(Korea)

Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns （forest, agriculture and urban） using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams （289.6 mg N20-N m-2 d-1）〉 urban streams （157.0 mg N20-N m-2 d-1）〉 forested streams （41.9 mg N20-N m-2 d-l）. In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams.

关键词： denitrifier communities denitrifying genes nutrient cycle stream ecosystem

Constraints on Camel Meat and Milk Marketing and strategies for Its Improvement in Northern Kenya

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Journal of Agricultural science and Technology(A) 2011年第5期1卷 703-712页

作者： s. G. Kuria A. Omore I. N. Thendiu d. M. Mwangi A. B. Ngaanga s. Kaitibie Kenya Agricultural Research Institute P.O. Box 147-60500 Marsabit Kenya International Livestock Research Institute Nairobi Campus Kenya Ministry of Livestock development Headquarters HillPlaza Nairobi Kenya Kenya Agricultural Research Institute P.O. Box 57811-00200 Nairobi Kenya Kenya CamelAssociation HillPlaza Nairobi Kenya

A survey to identify constraints and design strategies to improve the camel milk and meat value chains was conducted in northern Kenya using Participatory Integrated Community development （PICd）, Focus Group discussions （FGd）, among other methods. In a second step, field testing of an intervention on milk and meat hygiene was carried out at household level. survey results indicated that about 50% of marketable camel milk was not sold, 30% of marketed camel milk per annum was sold in sour state at Us$ 0.13 lower that the price of a litre of fresh milk while processed meat got spoiled along the chain. Annual economic losses associated with milk spoilage were estimated at Us$ 961,538.5. Preliminary findings of the field testing indicated that an additional 3 million litres of camel milk was sold in fresh state, giving an annual saving of Us$ 384,615.4. Increased profitability of up to 60% compared to 30% before the intervention was reported among nyirinyiri processors. In conclusion, economic potential of the camel could be fully exploited by facilitating adoption of interventions such as hygiene, among others at all levels of the camel milk and meat value chains.

关键词： Value chains camel products economic potential pastoralists arid Kenya.

Optimum Protocol for shoot Formation in karandafi Red sorghum (<i>sorghum bicolor</i>(L.) Moench) through somatic Embryogenesis Using Mature Embryo

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American Journal of Plant sciences 2014年第5期5卷 671-675页

作者： Lateefat Bolanle Hassan Inuwa s. Usman Mary d. Katung sanusi M. Bugaje department of Plant science Ahmadu Bello University Zaria Nigeria

In this study, an optimum protocol for shoot formation through somatic embryogenesis using mature embryo explants was developed. Calli were initiated on Murashige and skoog (Ms) media supplemented with varying concentration of 2,4-dichlorophenoxyl acetic acid (2,4-d) ranging from 1.5 mg/l-4.0 mg/l alone or in combination with 0.5 mg/l Kinetin (KN). significance difference (p 0.05) was observed among the different concentrations of hormone used for callus induction. The highest percentage callus formation was obtained from the media fortified with 4 mg/l 2, 4-d for mature embryo obtained from imbibed seed while for the preconditioned mature embryo, the media supplemented with 2 m/l 2,4-d + 0.5 mg/l kinetin (KN) recorded more percentage callus formation compared to what was obtained from the media supplemented with 2.5 mg/l2,4-d + 0.5 mg/l. More percentage shoot formation was obtained from the media supplemented with 1 mg/l 6-benzylaminopurine (BA). Average number of shoot per callus was also more in the media fortified with 1 mg/l BA (2.25) but this was not significantly different from what was obtained from the media fortified with 2 mg/l BA+ 0.1 mg/l 2,4-d at 5% level of significance.

关键词： sorghum bicolor Callus Induction In-Vitro Regeneration

simplified seismic fatigue evaluation for rigid steel connections

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 245-253页

作者： AymanA.shama John B.Mander stuart.s.Chen Parsons Corporation 100 BroadwayNew York.NY 10005USA Ph.D.P.E department of Civil Engineering University of CanterburyNew Zealand Professor department of Civil Structural & Environmental EngineeringState University of New York at BuffaloBuffaloNY 14260USA Associated Professor

A simplified fatigue-life model is proposed for assessing the seismic inelastic rotational capacity of steel *** relations are developed for rigid steel connections under lateral *** this is extended to account for the effects of the welded steel moment frame(WsMF)connections of the so-called pre-Northridge *** seismic fatigue theory is validated against experimental *** experiments were conducted under increasing ductility amplitudes until the onset of ***'rule was used to convert the test results to given an equivalent constant amplitude cyclic fatigue *** agreement is obtained when comparing the experimental observations with the theoretical predictions.

关键词： fatigue cyclic load seismic pile-to-cap moment frames connections steel

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胰腺导管腺癌漏诊及误诊病例的相关因素分析

国际医学放射学杂志 2021年第3期44卷 371-372页

作者： J.d.Kang s.E.Clarke A.F.Costa 师博

摘要目的回顾性分析漏诊或误诊的胰腺导管腺癌(PdAC)的超声、CT和MR影像学表现,识别影响PdAC检出和诊断的因素。方法回顾性分析2014—2015年诊断为

关键词：

BAsIsITY PROBLEM ANd WEIGHTEd sHIFT OPERATORs

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Acta Mathematica scientia 2014年第5期34卷 1655-1660页

作者： M.GRdAL M.T.GARAYEV s.sALTAN suleyman demirel University Department of Mathematics department of Mathematics College of Science King Saud UniversityP.O.Box 2455 Riyadh 11451 Saudi Arabia

We investigate a basisity problem in the space =lpA（d）and in its invariant sub-spaces. Namely, let W denote a unilateral weighted shift operator acting in the spacelpA（d）, 1≤p《∞, by W zn=λnzn＋1, n≥0, with respect to the standard basis λzn＋1 n≥0. Applying the so-called ＂discrete duhamel product＂ technique, it is proven that for any integer k ≥1 the sequence {（wi＋nk）-1｜W ｜Ei）knf}n≥0 is a basic sequence in Ei ：=span{zi＋n ：n≥0} equivalent to the basis {zi＋n}n≥0 if and only if fb（i） 6= 0. We also investigate a Banach algebra structure for the subspaces Ei, i≥0.

关键词： basis basic sequence discrete duhamel product Banach algebra weightedshift operator