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动物粪便的利用

草食家畜 1984年第S1期 20-29页

作者： J.P.Fonteno,L.W.Smith,A.L.Sutton,熊易强 Dept.of Anim.Sci. VPI and State univ. Ruminant Nutrition Lab. USDA Beltsville MD Dept.of Anim.Sci. purdue univ.

75年前动物粪便被认为是一种有价值的肥料来源。随着集约化动物生产系统的出现,粪便成了污染物和有害物。而在过去的几年中,动物粪便又重新被视为有价值的资源。动物粪便的主要利用途径是作为植物营养物（肥料）、动物营养物（饲料）和... 详细信息

75年前动物粪便被认为是一种有价值的肥料来源。随着集约化动物生产系统的出现,粪便成了污染物和有害物。而在过去的几年中,动物粪便又重新被视为有价值的资源。动物粪便的主要利用途径是作为植物营养物（肥料）、动物营养物（饲料）和能量（甲烷）生成原料的来源。动物粪便是植物所需营养物质的有价值的来源,而且提供有机物以改良土壤结构。由于动物粪便通常含纤维和非蛋白氮较高,用其饲喂反刍动物较之饲喂非反刍动物更有价值。饲喂前,粪便需经过加工处理以提高其适口性并破坏可能存在的病原体。现已成功地使用了许多加工方法。饲喂加工处理过的含有治疗用药物的粪便,只要掌握停喂时间,对健康的危害极小。粪便可通过嫌气发酵用于生成甲烷（CH4）。粪便用做家畜饲料的价值最高,而用于甲烷生成的价值最低。当甲烷生成的残余物用微肥料或饲料时,粪便的价值可进一步提高。当前有相当数量的粪便被用做饲料、肥料和甲烷生成,但其利用效率尚未达到最优化。关于动物粪便利用,需要应用系统分析原理,进行多学科的联合研究。需要在如何有效地防止营养成分在贮藏和施用于土壤中的损失方面进行进一步的研究。对于氮素的保存应予以特殊的注意。需要研究用做饲料的粪便保存问题。对养分,特别是矿物质的利用效率问题值得注意

关键词：动物粪便植物粪便处理废物处理反刍动物

A method to perform prognostics in electro-hydraulic machines: the case of an independent metering controlled hydraulic crane

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International Journal of Hydromechatronics 2018年第2期1卷 2-2页

作者： Yuri Ghini Andrea Vacca purdue univ Maha Fluid Power Res Ctr W Lafayette IN 47907 USA

Remaining useful life (RUL) estimation is a topic that has gained more and more attention in the field of fluid power systems, thanks to the tremendous potentials shown for improving safety and reduced production losses. However, many challenges related to RUL estimation are not solved yet, mainly connected to the definition of the health status of each component. A prognostic method based on a data-driven methodology for hydraulic systems is here proposed to estimate the percentage of life already spent by the monitored components. The potentials of the methodology are shown considering the case of a truck-mounted hydraulic crane, for which a simulation model was available.

关键词： perform prognostics electro-hydraulic machines independent metering controlled hydraulic crane

A lumped parameter vane pump model for system stability analysis

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International Journal of Hydromechatronics 2018年第3期1卷 1-1页

作者： Ryan P.Jenkins Monika Ivantysynova purdue univ Sch Mech Engn Maha Fluid Power Res Ctr 225 South Univ St W Lafayette IN 47905 USA purdue univ Dept Agr & Biol Engn Maha Fluid Power Res Ctr 225 South Univ St W Lafayette IN 47905 USA

This paper presents a semi-empirical lumped parameter model developed for analysing the dynamic stability and performance limitations of a pressure compensated vane pump for an automotive application with low-cost *** model calculates continuous displacement chamber pressure profiles and inertial effects for the determination of the internal forces acting on the vane pump's pivoting *** conducted on a custom test stand were used to define a nonlinearly progressive bias spring model and a black box representation of the pump control system *** of the complete model reveals that the performance limitations imposed by the control system valves,in terms of system stability and achievable controller bandwidth,are more restrictive than the limitations imposed by the low-cost vane pump and limit the that bandwidth to 1.84 *** control system also imposes limitations to the system performance based on resonance phenomena which may be significant in some applications.

关键词： presents semi-empirical lumped parameter chamber

交替冻融对土壤临界剪切力和土壤细沟可蚀性的影响

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水土保持研究 2021年第3期28卷 19-24页

作者：魏宁魏霞 Huang Chihua 西北农林科技大学理学院陕西杨陵712100 兰州大学资源环境学院兰州730000 Agronomy Dep. Purdue Univ.and USDA-ARS National Soil Erosion Research Lab.275S Russell StWest LafayetteIN 47907-2077USA

为了揭示冻融作用对土壤临界剪切力和细沟土壤可蚀性的影响,为冻融作用影响下的土壤侵蚀预报提供科学依据,通过室内交替冻融循环试验和变流量微型"V"型水槽人工放水冲刷试验,研究了交替冻融作用影响下土壤临界剪切力和土壤细沟可蚀性的... 详细信息

为了揭示冻融作用对土壤临界剪切力和细沟土壤可蚀性的影响,为冻融作用影响下的土壤侵蚀预报提供科学依据,通过室内交替冻融循环试验和变流量微型"V"型水槽人工放水冲刷试验,研究了交替冻融作用影响下土壤临界剪切力和土壤细沟可蚀性的变化特征。试验设计了参照试验(CK),3种交替冻融循环周期处理(1,3,6)和2种土壤质量含水率水平(10%,20%)。结果表明:不同试验处理对土壤临界剪切力和土壤细沟可蚀性的影响程度和趋势不同。当冻融循环周期为1时,土壤的临界剪切力和土壤细沟可蚀性相比参照试验呈现增大的趋势;当冻融循环周期继续增大至3,6时,土壤的临界剪切力和土壤细沟可蚀性相对于参照试验呈减小趋势。当冻融循环周期相同时,10%含水率水平下的土壤临界剪切力和土壤细沟可蚀性均大于20%含水率水平下的土壤临界剪切力和土壤细沟可蚀性。研究为冻融作用影响下土壤侵蚀的预报提供重要参考。

关键词：冻融作用变流量冲刷土壤临界剪切力土壤细沟可蚀性

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Background and Research Prospect of Geo-ecological Survey and Monitor in the Critical Zone of Black Soil

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 126-129页

作者： LI Zhizhong WANG Daming DAI Huimin WANG Xisheng LIANG Shuai XU Jiang YANG Jiajia WANG Lei CHEN Shengbo A lecos DEMETRIADES Veronika KOPACKOVA Igor SAVIN Douglas A.HOWARD Timothy FILLEY GENG Xiaoyuan Shenyang Geological Survey of China Geological Survey Shenyang 110030LiaoningChina China Geological Survey Beijing 100000China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100000China British Geological Survey Ctr Environm SciNottingham NG125GGEngland Jilin university Institute of Geology and Mineral Exploration Olympic VillageChangchun 130026JilinChina Czech Geological Survey Remote Sensing DepartmentPrague11821Czech Republic Russian Academy of Sciences Kirensky Institute of Physics Krasnoyarsk660036Russia Department of Geology Arizona State university TempeArizona85287-1404USA purdue univ Dept Earth Atmospher&Planetary Sci550 Stadium Mall DrW LafayetteIN 47907USA Kentville Research and Development Centre Agriculture and Agri-Food CanadaKentvilleNS B4N 1J5Cancda

The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the *** to the basics,breadth and the influence,25 of the issues which considered to be the most important were screened,including"How many people can the Earth carry?"(Stokstad,2005;Dailyg et al.,1992;Cohen,1995)and"How high will the greenhouse effect make the earth temperature?

关键词： black soils resource black soil critical zone earth critical zone

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