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Integrated management of natural resources in the Ecuador Highlands

Agricultural Sciences 2012年第5期3卷 768-779页

作者： víctor Hugo Barrera luis Orlando Escudero Jeffrey Alwang Robert Andrade Gordon INIAP Quito Ecuador Institute Department of Agricultural and Applied Economics virginia Polytechnic Institute and State University Blacksburg Virginia USA Institute Department of Agricultural and Applied Economics virginia Polytechnic Institute and State University Blacksburg VirRobert ginia USA

The Andean region of Ecuador is characterized by extreme poverty caused by low agricultural productivity, limited off-farm opportunities, and lack of access to markets. Poverty is related to degradation of natural resources as lagging agricultural productivity leads to incursions into fragile areas and use of erosive farming techniques on steeply sloped hillsides. Food production in fragile areas degrades soil and water resources, contributes to deforestation and loss of biodiversity, and reduces productive potential over time. This article discusses an agricultural development project designed to reduce the long-term downward development spiral in a watershed in Bolivar, Ecuador. The applied research program began with analysis of the state of soil resources, water, and biodiversity in the Chimbo sub-watershed. This information was used to design a plan with the input of local stakeholders to introduce environmentally friendly farming practices, soil and water conservation techniques, and various institutional innovations to promote resource conservation. This adaptive management program has been a solid success. This article describes the project, the challenges it faced, and how the process of adaptive management led to consensus among stakeholders about the appropriateness of sustainable management practices. We show how implementation of enhanced management practices contribute to reduced environmental vulnerability and improved welfare.

关键词： Component Natural Capital Micro-Watershed Systems Approach Adaptive and Integrated Watershed Management

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Esterification of levulinic acid to n-butyl levulinate over heteropolyacid supported on acid-treated clay

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Journal of Natural Gas Chemistry 2011年第1期20卷 18-24页

作者： S. Dharne v. v. Bokade Catalysis Division National Chemical Laboratory (CSIR)

Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid （HPA） supported on acid-treated clay montmorillonite （K10）. 20% （w/w） dodecatungestophosphoric acid （DTPA） supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% （w/w） DTPA/K10 for optimization of the activity.

关键词： levulinic acid n-butanol dodectungestophosphoric acid K10 n-butyl levulinate

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Synthesis and photoluminescence studies of Ba(Gd,Ln)B_9O_(16):Eu^(3+)(Ln=La,Y) phosphors for n-Uv LED lighting and display devices

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Journal of Rare Earths 2015年第2期33卷 140-147页

作者： v.v.Rangari S.J.Dhoble Department of Physics RTM Nagpur University

BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（SEM） and photoluminescence properties were investigated. The as-synthesized BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd^3＋ by La^3＋ and Y^3＋ ions in the host BaGdB9O16：Eu^3＋ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba（Gd,Ln）B9O16（Ln=La, Y） phosphors were promising red phosphors, which might find potential applications in near-Uv excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL（compact fluorescent lamp） was also done. Energy transfer mechanism of Gd^3＋ to Eu^3＋ was also discussed in this paper.

关键词： phosphor solid state diffusion display devices photoluminescence rare earths

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Experience gained in analyzing severe accidents for WWER RP using CC SOCRAT

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Frontiers in Energy 2021年第4期15卷 872-886页

作者： S.I.PANTYUSHIN А.v.LITYSHEv A.v.NIKOLAEvA O.v.AULOvA D.L.GASPAROv v.v.ASTAKHOv M.A.BYKOv Non-stationary Thermohydraulics Department OKB Gidropress JSC 142103PodolskRussia

The current Russian regulatory documents on the safety of nuclear power plant(NPP)specify the requirements regarding design basis accidents(DBAs)and beyond design basis accidents(BDBAs),including severe accidents(SAs)with core meltdown,in NPP design(NP-001-15,NP-082-07,and others).For a rigorous calculational justification of BDBAs and SAs,it is necessary to develop an integral CC that will be in line with the requirements of regulatory documents on verification and certification(RD-03-33-2008,RD-03-34-2000)and will allow for determining the amount of data required to provide information within the scope stipulated by the requirements for the structure of the safety analysis report(SAR)(NP-006-16).The system of codes for realistic analysis of severe accidents(SOCRAT)(formerly,thermohydraulics(RATEG)/coupled physical and chemical processes(SvECHA)/behavior of core materials relocated into the reactor lower plenum(HEFEST))was developed in Russia to analyze a wide range of SAs at NPP with water-cooled water-moderated power-generating reactor(WWER)at all stages of the *** to the code and broadening of its applicability are continually being pursued by the code developers(Nuclear Safety Institute of the Russian Academy of Sciences(IBRAE RAN))with OKB Gidropress JSC and other ***,the SOCRAT/В1 code can be used as a base tool to obtain realistic estimates for all parameters important for computational justification of the reactor plant(RP)safety at the in-vessel stage of SAs with fuel *** perform analyses using CC SOCRAT/В1,the experience gained during execution of thermohydraulic codes is applied,which allows for minimizing the uncertainties in the results at the early stage of an accident *** study presents the results of the work performed in 2010–2020 in OKB Gidropress JSC using the CC SOCRAT/В*** have been considered to develop calculational models and analyze SAs using CC *** process,which is cle

关键词： system of codes for realistic analysis of severe accidents(SOCRAT) design basis accidents(DBAs) severe accidents(SAs) computer code(CC) nuclear power plant(NPP)design water-cooled water-moderated(WWER) modeling model safety requirements

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Influence of Turbulence Intensity and Turbulence Length Scale on the Drag, Lift and Heat Transfer of A Circular Cylinder

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China Ocean Engineering 2017年第3期31卷 357-363页

作者： I.v. Morenko v.L. Fedyaev Institute of Mechanics and Engineering Kazan Science Center Russian Academy of Sciences (IME KazSC RAS) Kazan Russian Federation Kazan National Research Technical University named after A.N. Tupolev - KAI (KNRTU-KAI) Kazan Russian Federation

Influence of the turbulence intensity and turbulence length scale on the hydrodynamic characteristics and heat transfer of a circular cylinder, streamlined by a viscous fluid flow, is numerically studied. We take the Reynolds number of the oncoming flow equal to 4×10^4, the turbulence intensity Tuf and the dimensionless turbulence length scale L-f varying from 1.0% to 40% and from 0.25 to 4.0, respectively. We confirmed that the increase of Tuf leads to the suppression of the periodic vortex shedding from the cylinder surface, and as a result the stationary mode of streamlining is formed. Consequently, with the increasing turbulence intensity directly in front of the cylinder Tu＊, the amplitude of the lift coefficient decreases monotonically. Nevertheless, the time-averaged drag coefficient of the streamlined cylinder decreases at Tu＊〈6.0%, and increases at Tu＊〉9.0%. The dependence of the average Nusselt number on Tu＊ is near-linear, and with the increasing turbulence intensity, the Nusselt number rises. However, the change of the average Nusselt number depending on L-f is non-monotonic and at Lf=l.0, the value reaches its maximum

关键词： hydrodynamics turbulence heat transfer of a circular cylinder

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Noise degradation system using Wiener filter and CORDIC based FFT/IFFT processor

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Journal of Central South University 2015年第10期22卷 3849-3859页

作者： Yasodai A Ramprasad A v Department of Electronics and Communication Engineering Vickram College of Engineering Department of Electronics and Communication Engineering K L N College of Engineering

On augmentation of past work, an effective Wiener filter and its application for noise suppression combined with a formed CORDIC based FFT/IFFT processor with improved speed were executed. The pipelined methodology was embraced for expanding the execution of the system. The proposed Wiener filter was planned in such an approach to evacuate the iteration issues in ordinary Wiener filter. The division process was supplanted by a productive inverse and multiplication process in the proposed design. An enhanced design for matrix inverse with reduced computation complexity was executed. The wide-ranging framework processing was focused around IEEE-754 standard single precision floating point numbers. The Wiener filter and the entire system design was integrated and actualized on vIRTEX 5 FPGA stage and re-enacted to approve the results in Xilinx ISE 13.4. The results show that a productive decrease in power and area is developed by adjusting the proposed technique for speech signal noise degradation with latency of n/2 clock cycles and substantial throughput result per every 12 clock cycles for n-bit precision. The execution of proposed design is exposed to be 31.35% more effective than that of prevailing strategies.

关键词： Wiener filter iterations power spectrum FFT/IFFT floating point noise suppression speech enhancement vLSI speed power area

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Evolution of Microstructure and Texture during Hot Deformation of a Commercially Processed Supral100

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Journal of Materials Science & Technology 2012年第6期28卷 531-536页

作者： v. Huang BCAST Brunel University Kingston Lane Uxbridge UB8 3PH UK

The microstructure and texture in a commercially processed AI-6 wt% Cu-0.4 wt% Zr （Suprall00） aluminium alloy have been investigated after annealing and hot tensile straining at 450℃, using a field emission gun scanning electron microscope （SEM） and electron backscatter diffraction （EBSD）. The microstructure of commercially processed alloy had a relatively large fraction of high angle grain boundaries （HAGBs） which were aligned parallel to the rolling direction, and a strong texture. Annealing at 450℃ led to an increase in the fraction of HAGBs and to an increase in HAGB spacing and these changes were progressively enhanced by subsequent tensile deformation. The increasing fraction of HAGBs was due to the annihilation of low angle grain boundaries （LAGBs）. A sharpening of texture during annealing was attributed to preferential textural growth, and the reduction of texture at higher tensile strains led to the development of superplastic behaviour. The present work supports the view that the evolution of the fine grain microstructure during the high temperature straining of SuprallO0 is primarily due to the accumulation of a large area of grain boundary during the initial thermomechanical processing, and does not involve any unusual restoration processes.

关键词： Aluminium Superplastic deformation Microstructure Texture Electronbackscatter diffraction

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Plasma Treatment of Aluminum Using a Surface Barrier Discharge Operated in Air and Nitrogen: Parameter Optimization and Related Effects

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Plasma Science and Technology 2013年第8期15卷 794-799页

作者： v. PRYSIAZHNYI Masaryk University Faculty of ScienceDepartment of Physical Electronics

This paper presents the results of aluminum surface treatment by diffuse coplanar surface barrier discharge. The goals are to study the effectiveness of the plasma treatment and the dependence of its efficiency on operation parameters, such as sample-to-electrode distance, treatment time or gas atmosphere. Three types of aluminum materials （bricks, sheets and thin films） were tested to ensure the reliability of the treatment. The changes in the surface properties were characterized by the surface free energy, atomic force microscopy, attenuated total reflectance Fourier transform infrared spectroscopy （ATR FTIR） and X-ray photoelectron spec- troscopy （XPS）. The influence of aging effect on the treatment was also measured and discussed.

关键词： aluminum surface treatment plasma treatment

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Influence of cobalt on performance of Cu-CeO2 catalysts for preferential oxidation of CO

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Journal of Rare Earths 2020年第9期38卷 941-950,I0001页

作者： Sachin Malwadkar Parthasarathi Bera C.v.v.Satyanarayana Catalysis Division CSIR-National Chemical LaboratoryPune 411008India Surface Engineering Division CSIR-National Aerospace LaboratoriesBengaluru 560017India

Copper and cobalt oxides supported on CeO2 were investigated for preferential oxidation of carbon monoxide(CO-PROX)in the presence of excess hydrogen and CO2.(Cuo)1-x(Co3 O4)x/3-(CeO2)2.5(x=0,0.25,0.50,0.75,0.85 and 1)catalysts were prepared by coprecipitation *** mixed oxide catalysts were characterized by several physicochemical techniques,such as BET surface area(SBET),X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),temperature programmed reduction(TPR)and X-ray photoelectron spectroscopy(XPS).XRD studies show the peaks related to CuO and Co3 O4 phases in copper and cobalt containing CeO2 *** average particle size of the CeO2 crystallites is in the range of 8-10 nm as evaluated from HRTEM *** studies demonstrate that Cu,Co and Ce in(cuO)1-x(Co3O4)x/3-(CeO2)2.5 catalysts are presented in+2 and+1,+3 and+2 and+4 and+3 oxidation states,*** catalyst with x=0.75 shows better activity and selectivity towards *** the catalyst with only copper(CuO-CeO2,x=0)shows good activity but reverse water gas shift(RWGS)reaction is noticed at high *** the other hand,RWGS reaction is suppressed on the cobalt containing CuO-ceO2 *** on CeO2 with x=1 shows hardly any activity for PRoX reaction at low *** methanation activity is observed on CuO-CeO2 or Co3O4-CeO2 *** contrast,combination of copper and cobalt on CeO2 shows methanation of CO where enhanced activity is observed with increasing in cobalt content.

关键词： CO-PROX Cu-CeO2 XRD XPS Methanation H2O addition

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Thiopurine-methyltransferase variants in inflammatory bowel disease:Prevalence and toxicity in Brazilian patients

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World Journal of Gastroenterology 2014年第12期20卷 3327-3334页

作者： Ana Teresa P Carvalho Barbara C Esberard Renata S B Fróes Davy C M Rapozo Ana B Grinman Tatiana A Simo Juliana C v C Santos Antonio José v Carneiro luis Felipe Ribeiro-Pinto Heitor S P de Souza Disciplina de Gastroenterologia e Endoscopia Digestiva Universidade do Estado do Rio de Janeiro Programa de Carcinogênese Molecular Instituto Nacional de Cancer Laboratório de Toxicologia e Biologia Molecular Universidade do Estado do Rio de Janeiro Servi?o de Gastroenterologia Departamento de Clínica MédicaUniversidade Federal do Rio de Janeiro

AIM: To analyze the prevalence of thiopurine-methyltransferase (TPMT) genotypes and their association with drug toxicity in inflammatory bowel disease (IBD) patients from southeastern Brazil.

关键词： Inflammatory bowel disease Thiopurine-methyl-transferase Azathioprine Drug toxicity Pancreatitis

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