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Mitigating nitrous oxide emissions from agricultural soils by precision management

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Frontiers of Agricultural Science and En.ineering 2020年第1期7卷 75-80页

作者： Robert M.REES Juliette MAIRE Anna FLOREnCE nicholas COWAn Ute SKIBA Tony van der WEERDEn Xiaotang JU Scotland's Rural College EdinburghScotlandEH93JGUK Centre for Ecology and Hydrology Bush EstatePenicuikScotlandEH26 OQBUK AgResearch Invermay Agricultural CentreMosgiel 9053New Zealand College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

nitrous oxide(n2O)emissions make up a significant part of agricultural greenhouse gas *** is an urgent need to identify new approaches to the mitigation of these emissions with emerging *** this short review four approaches to precision managements of agricultural systems are described based on examples of work being undertaken.in the UK and new *** offer the opportunity for n2 O mitigation without any reduction.in *** approaches depend upon new sensor technology,modeling and spatial information with which to make management decisions and interventions that can both improve agricultural productivity and environmental protection.

关键词： decision support systems mitigation nitrous oxide precision farming

DIFFUSIVE-DISPERSIVE TRAVELInG WAVES AnD KInETIC RELATIOnS IV. COMPRESSIBLE EULER EQUATIOnS

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Chinese Annals of Mathematics,Series B 2003年第1期24卷 17-34页

作者： n. BEDJAOUI P.G.LEFLOCH Centre de Mathematiques Appliquees & Centre national de la Recherche Scientifique UMR 7641 Ecole Polytechnique 91128 Palaiseau Cedex France. INSSET Universite de Picardie 48 rue Raspail 02109 Saint-Quentin France.Centre de Mathematiques Appliquees & Centre National de la Recherche Scientifique UMR 7641 Ecole Polytechnique 91128 Palaiseau Cedex France.

The authors consider the Euler equations for a compressible fluid in one space dimensionwhen the equation of state of the fluid does not fulfill standard convexity assumptions andviscosity and capillarity effects are taken.into account. A typical example of nonconvex con-stitutive equation for fluids is Van der Waals' equation. The first order terms of these partialdifferential equations form a non.inear system of mixed (hyperbolic-elliptic) type. For a class ofnonconvex equations of state, an existence theorem of traveling waves solutions with arbitrarylarge amplitude is established here. The authors distinguish between classical (compressive) andnonclassical (undercompressive) traveling waves. The latter do not fulfill Lax shock inequali-ties, and are characterized by the so-called kinetic relation, whose properties are investigatedin this paper.

关键词： Elasto dynamics Phase transitions Hyperbolic conservation law Diffusion Dispersion Shock wave Undercompressive Entropy inequality Kinetic relation

论热带作物的稳定抗病性育种:现代农业保持植物/病害系统平衡的策略

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世界热带农业信息 1980年第5期 21-24页

作者： n.A.Van der Graaff 余卓桐

现代的农作物生产应以生物系统的管理为其特征。即使应该承认病害是不能消灭的,也应当通过使所出现的寄生物只能造成微小损害的方式来保持寄主/寄生物(包括害虫)系统的平衡。如果我们将野生植物/病原体系统(包括害虫)和原始作物系统与... 详细信息

现代的农作物生产应以生物系统的管理为其特征。即使应该承认病害是不能消灭的,也应当通过使所出现的寄生物只能造成微小损害的方式来保持寄主/寄生物(包括害虫)系统的平衡。如果我们将野生植物/病原体系统(包括害虫)和原始作物系统与现代农业系统相比较,就可以得到有关寄主与寄生物的关系的一些有用的见识。在现代农业中,可以利用这些见识来管理寄主/寄生

关键词：水平抗病性寄主寄生物咖啡树埃塞俄比亚病原菌垂直抗性抗病育种抗性育种叶锈病褐锈病苦腐病腐烂病遗传变异性田间观察作物农业植物

云南梅树村前寒武系—寒武系界线层型候选剖面的古地磁研究

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地质学报 1990年第3期64卷 264-274页

作者：梁其中方武 Rob Van der Voo 云南省地质科学研究所美国密西根大学地质系

梅树村剖面,已被推荐为国际前寒武系—寒武系界线层型候选剖面。本文论述了对该剖面进行的古地磁研究,在剖面的碳酸盐及磷酸盐台地相地层中,依次采集了159块古地磁样品。热退磁结果表明:剖面中的大多数岩石已被现今地磁场强烈重磁化,但... 详细信息

梅树村剖面,已被推荐为国际前寒武系—寒武系界线层型候选剖面。本文论述了对该剖面进行的古地磁研究,在剖面的碳酸盐及磷酸盐台地相地层中,依次采集了159块古地磁样品。热退磁结果表明:剖面中的大多数岩石已被现今地磁场强烈重磁化,但仍有57块样品保存有呈互为对踱的剩磁方向(平均D/l=4.2°/7.1°,K=9,α_(95)=6.6。),并计算出古地磁极位置为68.8°n,270.7°E。这与华南年轻的显生宙岩石所得到的极位置皆不一样。该项研究的结果构成一极性带,至少有9次倒转。此极性带与苏联西伯利亚,澳大利亚及美国西部所获得的资料对比,都共同显示出以频繁的极性倒转为特征。

关键词：前寒武纪寒武纪候选剖面古地磁

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温暖的内心德国ZUM LOWEn酒店

室内设计与装修 2014年第2期 18-19页

作者： Anja Müller Hans Georg n.der

当你踏入ZUMLoWEn酒店，那感觉就像你进入一个亲密的朋友的家。与所有舒适的传统德国酒店相同，坐落在下萨克森的ZUMLOWEn酒店无疑是中世纪的历史瑰宝。整个木结构建筑位于杜德施塔特城的中心，这个从中世纪兴盛起来的古城，赋予了酒店... 详细信息

当你踏入ZUMLoWEn酒店，那感觉就像你进入一个亲密的朋友的家。与所有舒适的传统德国酒店相同，坐落在下萨克森的ZUMLOWEn酒店无疑是中世纪的历史瑰宝。整个木结构建筑位于杜德施塔特城的中心，这个从中世纪兴盛起来的古城，赋予了酒店一个难以忽略的历史胎记。

关键词：酒店德国内心温暖木结构建筑历史舒适古城

Experimental Study of Soot Volume Fraction Applied in Laminar Diffusion Flames

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Modern Mechanical En.ineering 2013年第4期3卷 137-141页

作者： n. R. Caetano F. M. Pereira H. A. Vielmo F. T. van der Lann Federal University of Rio Grande do Sul DEMEC-UFRGS Porto Alegre Brazil

The soot emission has been the focus of many studies due to applications in.industry and the prejudicial effects caused to the environment. The presence of soot is important to the heat transfer in boilers and combustion chambers, contributing significantly to efficiency increases. In controversy, the inhaled soot may cause respiratory system damage and even cancer. Another important point is the contribution to the greenhouse effect. Therefore, the aim of this work is to analyse the soot emission.in laminar diffusion flames produced from commercial fuels stabilized on a burner representative of industrial applications. Methane, vehicular natural gas and liquid petroleum gas are considered as fuels. An experimental setup was constructed to implement the technique of laser light extinction and laser-induced incandescence. These non.intrusive techniques provide instant information, in real time, about soot volume fraction. The measurements were calibrated and validated using methods and results of studies available in the literature, and also the uncertainty is analysed and suitably minimized. The results will contribute to the database for projects of combustion systems optimization, aiming to increase the efficiency and soot emissions control.

关键词： Soot Emissions Laminar Diffusion Flames Commercial Fuels

Impact of age on transcatheter aortic valve implantation outcomes：a comparison of patients aged≤ 80 years versus patients ＆gt; 80 years

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Journal of Geriatric Cardiology 2016年第1期13卷 31-36页

作者： Frank van der Kley Philippe J van Rosendael Spyridon Katsanos Vasileios Kamperidis nina A Marsan Ioannis Karalis Arend de Weger Meindert Palmen Jeroen J Bax Martin J Schalij Victoria Delgado Heart Lung Center Leiden University Medical Center Leiden the Netherlands

ObjectiveTo investigate the procedural outcomes and the long-term survival of patients undergoing transcatheter aortic valve implantation （TAVI） and compare study results of patients≤ 80 years and patients ＆gt; 80 years *** total of 240 patients treated with TAVI were divided into two groups according to age≤ 80 years （n = 105; 43.8%） and ＆gt; 80 years （n= 135; 56.2%）. The baseline characteristics and the pro-cedural outcomes were compared between these two groups of *** the exception of peripheral artery disease and hypercho-lesterolemia, which were more frequently observed in the older age group, baseline characteristics were comparable between groups. Complica-tion rates did not differ significantly between patients≤ 80 years and patients ＆gt; 80 years. There were no differences in 30-day mortality rates be-tween patients aged≤ 80 years and patients ＆gt; 80 years old （9.5%vs. 7.4%, respectively;P = 0.557）. After a median follow-up of 28 months （in-terquartile range： 16-42 months）, 50 （47.6%） patients aged≤ 80 years died compared to 57 （42%） deaths in the group of patients ＆gt; 80 years old （P= 0.404）.ConclusionThe results of the present single center study showed that age did not significantly impact the outcomes of TAVI.

关键词： Age Survival rate Transcatheter aortic valve implantation

Optimizing the oxide support composition.in Pr-doped CeO_(2) towards highly active and selective ni-based CO_(2) methanation catalysts

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Journal of Energy Chemistry 2022年第8期31卷 547-561,I0015页

作者： Anastasios I.Tsiotsias nikolaos D.Charisiou Ayesha AlKhoori Safa Gaber Vlad Stolojan Victor Sebastian Bart van der Linden Atul Bansode Steven J.Hinder Mark A.Baker Kyriaki Polychronopoulou Maria A.Goula Laboratory of Alternative Fuels and Environmental Catalysis(LAFEC) Department of Chemical EngineeringUniversity of Western MacedoniaGR-50100Greece Department of Mechanical En.ineering Khalifa University of Science and TechnologyAbu DhabiP.O.Box 127788United Arab Emirates Center for Catalysis and Separations Khalifa University of Science and TechnologyAbu DhabiP.O.Box 127788United Arab Emirates Advanced Technology Institute Department of Electrical and Electronic EngineeringUniversity of SurreyGuildford GU24DLUK Department of Chemical En.ineering and Environmental Technology Universidad de ZaragozaCampus Río Ebro-Edificio I+D50018 ZaragozaSpain Instituto de nanociencia y Materiales de Aragón.inMA) Universidad de Zaragoza-CSICc/María de Luna 350018 ZaragozaSpain networking Research Center on Bioen.ineering Biomaterials and NanomedicineCIBERBBN28029 MadridSpain Department of Chemical En.ineering Delft University of TechnologyVan der Massweg 92629 HZ DelftThe Netherlands The Surface Analysis Laboratory Faculty of Engineering and Physical SciencesUniversity of SurreyGuildford GU24DLUK

In this study,ni catalysts supported on Pr-doped Ce O_(2) are studied for the CO_(2) methanation reaction and the effect of Pr doping on the physicochemical properties and the catalytic performance is thoroughly *** is shown,that Pr^(3+)ions can substitute Ce^(4+)ones in the support lattice,thereby introducing a high population of oxygen vacancies,which act as active sites for CO_(2) *** doping can also act to reduce the crystallite size of metallic ni,thus promoting the active metal *** performance evaluation evidences the promoting effect of low Pr loadings(5 at%and 10 at%)towards a higher catalytic activity and lower CO_(2) activation *** the other hand,higher Pr contents negate the positive effects on the catalytic activity by decreasing the oxygen vacancy population,thereby creating a volcano-type trend towards an optimum amount of aliovalent substitution.

关键词： Power-to-gas CO_(2)methanation ni-based catalyst Pr-doped CeO_(2) Oxygen vacancy Catalytic activity Activation energy

A four parameter cubic equation of state with temperature dependent covolume parameter

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Chinese Journal of Chemical En.ineering 2019年第5期27卷 1132-1148页

作者： Pradnya n.P.Ghoderao Vishwanath H. Dalvi Mohan narayan Department of Physics Institute of Chemical TechnologyMumbai 400019India Department of Chemical En.ineering Institute of Chemical TechnologyMumbai 400019India

A four-parameter, Ghoderao–Dalvi–narayan 2 cubic equation of state(GDn2 CEOS), is presented which incorporates the following: 1. The experimental value of the critical compressibility factor has been used as a fixed input parameter for calculations;2. All the parameters(a, b, c, d) of CEOS are temperature dependent functions in the subcritical region and are temperature independent functions in the supercritical region and;3. A new α function is introduced with two compound specific parameters which are estimated by matching saturated vapor pressure at two fixed temperature points Tr= 0.5, 0.7. Our formalism enables us to cast three of the four parameters of the CEOS as a function of the remaining parameter. The proposed CEOS is used to predict properties of 334 pure compounds, including saturated vapor pressure and liquid density, compressed liquid density, heat capacities at the constant pressure and volume, enthalpy of vaporization, sound velocity. To calculate thermodynamic properties of a pure compound, the present CEOS require the critical temperature, the critical pressure, the Pitzer’s acentric factor, the critical compressibility factor, and two parameters of the alpha function. The saturated liquid density predictions for pure fluids are very accurate when compared with GDn1(Ghoderao–Dalvi–narayan 1),MPR(Modified Peng–Robinson), and PT(Patel–Teja) equations of state. Unlike MPR EOS, the proposed temperature dependent covolume parameter b in the present work satisfies all the constraints mentioned in the literature to avoid thermodynamic inconsistencies at the extreme temperature and pressure. Using van der Waals one-fluid mixing rule, the present CEOS is further used to predict bubble pressure and the vapor mole fraction of binary mixtures.

关键词： Phase equilibria Thermodynamic properties Vapor-liquid equilibria The cubic equation of state Covolume parameter Supercritical region