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Choices of Varieties and Demand for Improved Rice Seed in Fogera District of Ethiopia

Rice science 2018年第6期25卷 350-356页

作者： A.h.MESFIN l.ZEMEDU Agricultural Economics Research Ethiopian Institute of Agricultural Research/Agricultural Research Center Agricultural Economics Research Ethiopian Institute of Agricultural Research/Debrezeit Agricultural Research Center

In this study, 151 households were randomly drawn from three randomly selected kebele in probability proportional to size method. The demographic and socio-economic factors that determine the participation in improved varieties were household labor availability, education level of the household head,land holdings, distance to the nearest village market, proximity to the main market, and distance to access agricultural extension and access to the source of rice seeds. however, determinants of choice decision varied from cultivar to cultivar. The evidence of the study from the interdependence among the decision of adoption of improved rice varieties suggested that technology adoption will be accelerated by launching a progressively developing package and scheme of rice technology generation, and points to the importance of mobilising additional resources to augment households' efforts at popularization and promotion of improved rice *** findings from linearized Almost Ideal Demand Systems(lA/AIDS) model showed that compelling evidence for small proportion changes in own prices and cross price of improved rice varieties led to greater than unitary proportionate changes in their purchases. The results generally showed that farmers were very sensitive to changes in improved rice seed prices and incomes. The major implication of the findings was that any intervention to improve farmers' seed purchases should take into account efforts to increase farmers' purchasing power of agricultural inputs like improved seeds and fertilizers.

关键词： improved rice choice seed demand multivariate probit linearized Almost Ideal Demand Systems

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The combined effects of grain and sample sizes on the mechanical properties and fracture modes of gold microwires

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Journal of Materials Science & Technology 2019年第1期35卷 76-83页

作者： h.k.Yang k.Cao Y.han M.Wen J.M.Guo Z.l.Tan J.lu Y.lu hong kong Branch of National Precious Metals Material Engineering Research Center City University of Hong Kong Department of Mechanical and Biomedical Engineering City University of Hong Kong State key laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Sino-platinum Metals Co.Ltd Center for Advanced Structural Materials City University of Hong Kong Shenzhen Research Institute

hall-Petch relation was widely applied to evaluate the grain size effect on mechanical properties of metallic material. however, the sample size effect on the hall-Petch relation was always ignored. In the present study, the mechanical test and microstructure observation were performed to investigate the combined effects of grain and sample sizes on the deformation behaviors of gold microwires. The polycrystalline gold microwires with diameter of 16 ?m were annealed at temperatures from 100°C to 600°C, leading to different ratios(t/d) of wire diameter(t) to grain size(d) from 0.9 to 16.7. When the t/d was lower than 10, the yield stress dropped fast and deviated from the hall-Petch relation. The free-surface grains played key role in the yield stress softening, and the volume fraction of free-surface grains increased with the t/d decreasing. Furthermore, the effects of t/d on work-hardening behaviors and fracture modes were also studied. With t/d value decreasing from 17 to 3.4, the samples exhibited necking fracture and the dislocation pile-ups induced work-hardening stage was gradually *** the t/d value further decreasing(t/d he fracture mode turned into shear failure, and the work-hardening capability lost. As the gold microwire for wire bonding is commonly applied in the packaging of integrated circuit chips, and the fabrication of microwire suffers multi-pass cold-drawing and annealing treatments to control the grain size. The present study could provide instructive suggestion for gold microwire fabrication and bonding processes.

关键词： Gold microwire Wire bonding Tensile testing Grain size hall-Petch relationship

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Protective effect of Irsogladine on monochloramineinduced gastric mucosallesions in rats:a comparative study with rebamipide

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World Journal of Gastroenterology 1999年第6期5卷 477-482页

作者： h Yamamoto, M Umeda, h Mizoguchi, S kato and k Takeuchi kyoto Phamaceutical University 日本

AIM To examine the effect of irsogladine, a novel antiulcer drug, on the mucosal ulcerogenic response to monochloramine (Nh 2Cl) in rat stomach, in comparison with rebamipide, another antiulcer drug with cytoprotective activity. METhODS AND RESUlTS Oral administration of Nh 2Cl (120*!mM) produced severe hemorrhagic lesions in unanesthetized rat stomachs. Both irsogladine ( 1*!mg/*!kg - 10*!mg/*!kg , po ) and rebamipide ( 30*!mg/*!kg - 100*!mg/*!kg , po ) dose dependently prevented the development of these lesions in response to Nh 2Cl, the effect of irsogladine was significant at 3*!mg/*!kg or greater, and that of rebamipide only at 100*!mg/*!kg . The protective effect of irsogladine on Nh 2Cl induced gastric lesions was significantly reduced by N G nitro l arginine methyl ester (l NAME) but not by indomethacin, while that of rebamipide was significantly mitigated by indomethacin but not by l NAME. Topical application of Nh 2Cl (20*!mM) caused a marked reduction of potential difference (PD) in ex vivo stomachs. This PD reduction was not affected by mucosal application of irsogladine, but significantly prevented by rebamipide. The mucosal exposure to Nh 4Oh (120*!mM) also caused a marked PD reduction in the ischemic stomach (bleeding from the carotid artery), resulting in gastric lesions. These ulcerogenic and PD responses caused by Nh 4Oh plus ischemia were also significantly mitigated by rebamipide, in an indomethacin sensitive manner, while irsogladine potently prevented such lesions without affecting the PD response, in a l NAME sensitive manner. CONClUSION These results suggest that ① Nh 2Cl generated either exogenously or endogenously damages the gastric mucosa, ② both irsogladine and rebamipide protect the stomach against injury caused by Nh 2Cl, and ③ the mechanism underlying the protective action of irsogladine is partly mediated by endogenous nitric oxide, while that of rebamipide is in part mediated by endogenous prostaglandins.

关键词： irsogladine rebamipide monochloramine gastric mucosal lesions rats comparative study

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Multiscale and multiphysics explorations of the transient deposition processes and additive characteristics during laser 3D printing

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Journal of Materials Science & Technology 2021年第18期77卷 196-208页

作者： h.l.Wei F.Q.liu l.Wei T.T.liu W.h.liao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing.210094China State key laboratory of Solidification Processing Northwestern Poly technical UniversityXi'an710072China

laser directed energy deposition(DED)involves complex physical processes,and the trial and error examinations are time consuming and cost *** research paradigm can be reshaped using advanced phenomenological models via computing the spatiotemporal variations of the build *** this work,multi-layer and multi-track laser DED of Ti-6 Al-4 V were systematically explored on multiple scales including the 1D track,the 2D layer and the 3D full build considering the complex transport of energy,mass,and momentum in the moving freeform molten *** results showed that convex,nearflat,and wavy builds were generated using gradually larger hatch *** profiles of individual tracks and layers were extracted through the unique advantages of the *** individual tracks exhibited various patterns and rotated with specific inclinations to form distinct layer *** net increments of the deposit generated upon the printing of a new track during the continuous deposition process showed that the smaller hatch spacing caused higher overlap rate of horizontally adjacent tracks but lower remelting rate of vertically adjacent tracks in neighboring *** 3D numerical model was validated with corresponding experiments for various process *** scientific findings can provide useful insights for further researches of DED.

关键词： Additive manufacturing Multi-layer and multi-track Numerical model Build features Molten pool

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Magnesium Uptake and Palygorskite Transformation Abilities of Wheat and Oat

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Pedosphere 2012年第6期22卷 834-841页

作者： M.h.SAlEhI l.TAhAMTANI Department of Soil Science College of AgricultureShahrekord UniversityShahrekord(Iran)

Weathering of clay minerals is a source of nutrients to plants. Palygorskite is a Mg-rich fibrous clay mineral that commonly occurs in the soils and sediments of arid regions. Although many studies have examined the environmental conditions required for the formation and stability of palygorskite, information on the transformation of this mineral in the root zone （or rhizosphere） of agricultural crops is limited. This study explored the possibility of palygorskite transformation in the rhizosphere of wheat and oat and compared the ability of these crops to extract structural Mg from palygorskite. The crops were cultivated in pots consisting of a mixture of sand from hamadan region, Iran and Florida palygorskite, irrigated with distilled water, and treated with either complete or Mg-free nutrient solutions. After 100 d, Mg uptake by the crops was measured. Clay-sized particles in each pot were also separated from the sand and were analyzed through X-ray diffraction （XRD）. The X-ray pattern of the particles was compared with that of the pure palygorskite particles （before cultivation）. The results showed that palygorskite could provide sufficient Mg for the growth of wheat in the pots supplied with Mg-free nutrient solution. In spite of the magnesium uptake by both plants from the palygorskite structure, no detectable peaks indicating the transformation of pMygorskite were recognized by XRD. A decrease of 1.05 nm in peak intensity was more obvious for the pots containing palygorskite and irrigated with Mg-free nutrient solution than for the pots irrigated with complete nutrient solution. Although the decrease in peak intensity was greater for oat than wheat, indicating greater palygorskite weathering by oat, Mg uptake by oat was low, as evidenced by the deficiency symptoms observed.

关键词： clay minerals nutrient solution rhizosphere weathering X-ray diffraction

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Disaster Risk Resilience:Conceptual Evolution,key Issues,and Opportunities

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International Journal of Disaster Risk Science 2022年第3期13卷 330-341页

作者： Marie-hélène Graveline Daniel Germain Institut des Sciences de l’Environnement(ISE) Universitédu QuébecàMontréalMontréalH3C 3P8Canada Department of Geography Universitédu QuébecàMontréalMontréalH3C 3P8Canada

Resilience has become a cornerstone for risk management and disaster ***,it has evolved extensively both etymologically and conceptually in time and across scientific *** concept has been(re)shaped by the evolution of research and practice *** the opposite of vulnerability for a long time,resilience was first defined as the ability to resist,bounce back,cope with,and recover quickly from the impacts of *** avoid the possible return to conditions of vulnerability and exposure to hazards,the notions of post-disaster development,transformation,and adaptation(build back better)and anticipation,innovation,and proactivity(bounce forward)were then ***,resilience is characterized by a multitude of components and several *** present a selection of 25 components used to define resilience,and an interesting linkage emerges between these components and the dimensions of risk management(prevention,preparedness,response,and recovery),offering a perspective to strengthen resilience through the development of *** its potential,resilience is subject to challenges regarding its operationalization,effectiveness,measurement,credibility,equity,and even its ***,it offers applicability and opportunities for local communities as well as an interdisciplinary look at global challenges.

关键词： Community Disaster risk Resilience Sustainable development

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Solidification pathway and phase transformation behavior in a beta-solidified gamma-TiAl based alloy

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Journal of Materials Science & Technology 2019年第11期35卷 2652-2657页

作者： h.Xu X.B.li W.W.Xing l.Shu Y.C.Ma k.liu Institute of Metal Research Chinese Academy of SciencesShenyang 110016China MIIT key laboratory of Advanced Metallic and Intermetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing 210094China

The phase transformation behavior of an as-cast Ti-42Al-5 Mn(at.%)alloy after subsequent quenching from 1380℃to 1000℃was investigated based on the differential thermal analysis(DTA),electron probe micro analyzer-backscattered electrons(EPMA-BSE),transmission electron microscope(TEM)and X-ray diffraction(XRD).The results show that,the solidification path can be summarized as follows:liquid→liquid+β→β→β→α→β+α+γ→βo+α2+γ→βo+γ+α2/γ→βo+γ+α2/γ+βo,sec,with the phase transformationα→βtemperature(Tβ)=1311℃,phase transformationγ→βtemperature of(Tγsolv)=1231℃,phase transformationα2→αorβo→βtemperature(Tα2→α/Tβo→β)=1168 C,eutectoid temperature(Teut)=1132℃and T(α2/γ→βo,sec)≈1120℃.In comparison with Ti-42 Al alloy,the Teut and Tγsolv are slightly increased while both the Tp is decreased obviously by 5%Mn *** quenched from the temperature of 1380-1260℃,the martensitic transformationβ→α'could occur to form the needlelike martensite structure inβ*** kind of martensitic structure is much obvious with the increase of temperature from 1260℃to 1380℃.When the temperature is below Tγsolv(1231℃),theγgrains would nucleate directly from theβ*** the temperature slightly lower than T(eut)(1132℃),the dottedβ(o,sec)phases could nucleate in the lamellar colonies besides theγlamellae precipitated withinα2 ***,at room-temperature(RT),the alloy exhibits(po+α2+γ)triple phase with microstructure ofβo+lamellae+γ,of which the lamellar structure consists ofα2,γandβo,sec *** phase transformation mechanisms in this alloy,involvingβ→α',β→γ,α2→α2/γandα2→βo,sec were discussed.

关键词： Titanium aluminides Quenching Phase transformation Microstructure βphase

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Nonplanar flow-induced vibrations of a cantilevered PIP structure system concurrently subjected to internal and cross flows

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Acta Mechanica Sinica 2019年第6期35卷 1241-1256页

作者： Z.Y.liu T.l.Jiang l.Wang h.l.Dai Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China hubei key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

Pipe-in-pipe(PIP)structures are widely used in offshore oil and gas pipelines to settle thermal insulation issues.A PIP structure system usually consists of two concentric pipes and one softer layer for thermal insulation *** total response of the system is related to the dynamics of both pipes and the interactions between these two concentric *** the current work,a theoretical model for flow-induced vibrations of a PIP structure system is proposed and analyzed in the presence of an internal axial flow and an external cross *** interactions between the two pipes are modeled by a linear distributed damper,a linear distributed spring and a nonlinear distributed spring along the pipe *** unsteady hydrodynamic forces due to cross flow are modeled by two distributed van der Pol wake *** nonlinear partial differential equations for the two pipes and the wake are further discretized by the aid of Galerkin’s technique,resulting in a set of ordinary differential *** ordinary differential equations are further numeri cally solved by using a fourth-order Runge-kutta integration *** portraits,bifurcation diagrams,an Argand diagram and oscillation shape diagrams are plotted,showing the existence of a lock-in phenomenon and figure-of-eight *** PIP system subjected to cross flow displays some interesting dynamical behaviors different from that of a single-pipe structure.

关键词： Cantilevered PIP structure Theoretical model Flow-induced vibration Cross flow Internal flow

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Effect of turbulent atmosphere on the on-axis average intensity of Pearcey–Gaussian beam

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Chinese Physics B 2016年第6期25卷 264-269页

作者： F Boufalah l Dalil-Essakali h Nebdi A Belafhal laboratory of Nuclear Atomicand Molecular PhysicsDepartment of PhysicsFaculty of SciencesChouab Doukkali University

The propagation characteristics of the Pearcey–Gaussian（PG） beam in turbulent atmosphere are investigated in this *** Pearcey beam is a new kind of paraxial beam,based on the Pearcey function of catastrophe theory,which describes diffraction about a cusp *** using the extended huygens–Fresnel integral formula in the paraxial approximation and the Rytov theory,an analytical expression of axial intensity for the considered beam family is *** numerical results for PG beam propagating in atmospheric turbulence are given by studying the influences of some factors,including incident beam parameters and turbulence strengths.

关键词： turbulent atmosphere Pearcey–Gaussian beam catastrophe theory Rytov theory

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Discrepancies between clinical and autopsy findings in patients who had an acute stroke

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Stroke & Vascular Neurology 2022年第3期7卷 215-221页

作者： lilla hudák Attila Csaba Nagy Sarolta Molnár Gábor Méhes katalin Erzsébet Nagy lászlóOláh lászlóCsiba Department of Neurology University of Debrecen Faculty of MedicineDebrecenHungary Department of Preventive Medicine University of Debrecen Faculty of Public HealthDebrecenHungary Department of Pathology University of Debrecen Clinical CenterDebrecenHungary Doctoral School of Neuroscience University of Debrecen Faculty of MedicineDebrecenHungary

Objectives According to international observations,the incidence of clinical autopsies is declining worldwide,plummeting below 5%in the USA and many European *** is an unfavourable trend as,in 7%-12%of cases,recent clinicopathological studies found discrepancies that might have changed the therapy or the outcome if known *** previous large-scale observations have examined varied patient populations,we aimed to focus on the differences between the clinical and pathological diagnostic findings in only patients who had a *** and methods We assessed the postmortem non-neuropathological and neuropathological findings of 534 consecutive patients who had a stroke who passed *** neoplasms,pneumonias,thromboembolisms and haemorrhagic transformations revealed only by autopsy were considered severe abnormalities;in addition,benign abnormalities important from an educational or scientific point of view were also *** In 26 of the 534 cases(4.9%),the presence of systemic neoplasms had already been confirmed in the clinical stage;however,8(1.5%)malignant tumours were only detected during ***,80(15%)thromboembolic events,73(13.6%)pneumonias and 66(18%)haemorrhagic transformations were only diagnosed at *** hospital stay(from admission to death)resulted in fewer discrepancies between clinical and autopsy diagnosis of thromboembolic events and pneumonias(phile the type of acute stroke is reliably diagnosed with imaging techniques,postmortem autopsies are also important in patients who had a stroke as autopsies may reveal clinically silent diseases(eg,tumour),and contribute to knowing the actual incidence of stroke-related thromboembolic and pneumonia complications.

关键词： neoplasms clinical finding

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