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满足未来废气排放标准的柴油车可变气门传动方案

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汽车与新动力 2021年第5期4卷 72-77页

作者： [德]m.ELICKER [德]W.CHRISTGEN [德]J.KIYANNI [德]m.brauer 范明强(译) 不详

随着欧七排放法规的出台,预计氮氧化物(NOx)排放限值和真实行驶排放(RDE)法规将进一步加严。为了满足废气排放限值,冷起动阶段目前仍面临着一系列挑战。舍弗勒公司、捷豹路虎公司和IAV公司开展合作,借助可变气门机构实现了内部废气再循... 详细信息

随着欧七排放法规的出台,预计氮氧化物(NOx)排放限值和真实行驶排放(RDE)法规将进一步加严。为了满足废气排放限值,冷起动阶段目前仍面临着一系列挑战。舍弗勒公司、捷豹路虎公司和IAV公司开展合作,借助可变气门机构实现了内部废气再循环(iEGR)、二次排气门升程和米勒循环配气定时,以此对废气温度进行有效管理,并通过整机行驶循环试验证实了效果。

关键词：排放标准柴油机可变气门传动方案

Dietary mitigation of enteric methane emissions from ruminants:A review of plant tannin mitigation options

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Animal Nutrition 2020年第3期6卷 231-246页

作者： Byeng R.min Sandra Solaiman Heidi m.Waldrip David Parker Richard W.Todd David brauer United States Department of Agriculture(USDA) Agricultural Research Service(ARS)BushlandTX79012USA Tuskegee University TuskegeeAL36088USA

methane gas from livestock production activities is a significant source of greenhouse gas(GHG)emissions which have been shown to influence climate *** technologies offer a potential to manipulate the rumen biome through genetic selection reducing CH4 *** production may also be mitigated to varying degrees by various dietary intervention *** to reduce GHG emissions need to be developed which increase ruminant production efficiency whereas reducing production of CH4 from cattle,sheep,and *** emissions may be efficiently mitigated by manipulation of natural ruminal microbiota with various dietary interventions and animal production efficiency *** some CH4 abatement strategies have shown efficacy in vivo,more research is required to make any of these approaches pertinent to modern animal production *** objective of this review is to explain how anti-methanogenic compounds(e.g.,plant tannins)affect ruminal microbiota,reduce CH4 emission,and the effects on host ***,this review provides information relevant to understanding the impact of tannins on methanogenesis,which may provide a cost-effective means to reduce enteric CH4 production and the influence of ruminant animals on global GHG emissions.

关键词： Feed efficiency Greenhouse gas(GHG)emission methanogenesis Tannin Ruminant

Shoot and root traits in drought tolerant maize(Zea mays L.) hybrids

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Journal of Integrative Agriculture 2018年第5期17卷 1093-1105页

作者： ZHAO Jin XUE Qing-wu Kirk E Jessup HOU Xiao-bo HAO Bao-zhen Thomas H marek XU Wen-wei Steven R Evett Susan A O'Shaughnessy David K brauer Texas A&m AgriLife Research and Extension Center at Amarillo TX 79106 USA Department of Soil Water and Environmental Sciences University of Arizona AZ 85721 USA School of Science and Technology Xinxiang University Xinxiang 453003 P.R.China Texas A&m AgriLife Research and Extension Center at Lubbock TX 79403 USA USDA-ARS Conservation and Production Research Laboratory TX 79012 USA

This study aimed to investigate the differences in shoot and root traits, and water use and water use efficiency（WUE） in drought tolerant（DT） maize（Zea mays L.） hybrids under full and deficit irrigated conditions. A two-year greenhouse study was conducted with four hybrids（one conventional hybrid, 33D53Am, two commercial DT hybrids, P1151 Am, N75H, and an experimental hybrid, Exp HB） grown under two water regimes（I（100） and I（50）, referring to 100 and 50% of evapotranspiration requirements）. Under water stress, the hybids P1151 Am, N75, and Exp HB showed more drought tolerance and had either greater shoot dry weight or less dry weight reduction than the conventional hybrid（33 D53 Am）. However, these three hybrids responded to water stress using different mechanisms. Compared with the conventional hybrid, the two commercial DT hybrids（P1151 Am and N75H） had a smaller leaf area, shoot dry weight, and root system per plant. As a result, these hybrids used less water but had a higher WUE compared with the conventional hybrid. In contrast, the experimental hybrid（ExpHB） produced more shoot biomass by silking stage at both irrigation levels than all other hybrids, but it had relatively lower WUE. The hybrids demonstrated different drought response mechanisms that may require different irrigation management strategies. more investigation and validation are needed under field conditions and in different soil types.

关键词： drought tolerant hybrid rooting characteristics water use water use efficiency

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希腊首台电力机车——希腊Sprinter

大功率变流技术 1999年第2期 1-6页

作者： H.m.brauer 王渤洪德

希腊Sprinter是世界上功率为5mW等级的电力机车中质量最轻的,它以较轻的质量和轴重充实了Euro Sprinter机车家族。本文介绍了该机车设计工作的特点及内容广泛的试验大纲。

关键词：电力机车设计试验希腊铁路

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希腊高性能电力机车

大功率变流技术 1998年第1期 36-37页

作者： H.m.brauer 刘信君德

1996年1月,Hellenic铁路组织(OSE)向Siemens公司订购了6台高性能“EuroSprinter”电力机车,该机车由Krauss maffei公司(机械部分)和Siemens公司(电气部分)联合制造。目前已生产出两台,其余几台计划于1997年底完成。它标志着希腊引进了... 详细信息

1996年1月,Hellenic铁路组织(OSE)向Siemens公司订购了6台高性能“EuroSprinter”电力机车,该机车由Krauss maffei公司(机械部分)和Siemens公司(电气部分)联合制造。目前已生产出两台,其余几台计划于1997年底完成。它标志着希腊引进了电力牵引。目前,希腊只有很少一部分电气化线路。但几个月前签订了一个包括进一步将塞萨洛尼基至雅典的500km线路电气化的合同。

关键词：电力机车电气化希腊

含异氰酸侧基的寡聚物作为牙本质及其他组织的粘接剂

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四川大学学报(医学版) 1990年第3期 297-297页

作者： G.m.brauer

由异氰酸m-异丙烯基二甲基苄酯(TmI)、甲基丙烯酸α-异氰酸基乙酯(IEm)及各种不同的烯类单体通过自由基聚合反应合成了一系列含异氰酸基的低聚物.这些低聚物多数为粘稠液体.每一种低聚物通过测定折光率、红外光谱及异氰酸基含量进行了鉴... 详细信息

由异氰酸m-异丙烯基二甲基苄酯(TmI)、甲基丙烯酸α-异氰酸基乙酯(IEm)及各种不同的烯类单体通过自由基聚合反应合成了一系列含异氰酸基的低聚物.这些低聚物多数为粘稠液体.每一种低聚物通过测定折光率、红外光谱及异氰酸基含量进行了鉴定.当牙

关键词：异氰酸异氰化物寡聚物低聚物侧基粘接剂牙本质

卫星观测在全球细颗粒物浓度长期暴露评估中的应用

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环境与职业医学 2015年第8期32卷 801-805,F0004页

作者： Aaron van Donkelaar Randall V.martin michael brauer Brian L.Boys 王晓宇张伊人金泰廙 Department of Physics and Atmospheric Science Dalhousie University Halifax NovaScofia Canada Harvard-Smithsortian Center for Astrophysics Cambridge Massachusetts USA School of Environmental Health University of British Columbia. Vancouver. British Columbia Canada

[背景]十余年的卫星观测提供了全球细颗粒物（Pm2.5）人群暴露趋势和大小的信息。[目的]利用多个卫星的测量值推断的Pm：5浓度，建立和改进大气Pm2.5质量和趋势的全球暴露评估。[方法]结合3个卫星反演的Pm25源数据，得出1998-2012年10km... 详细信息

[背景]十余年的卫星观测提供了全球细颗粒物（Pm2.5）人群暴露趋势和大小的信息。[目的]利用多个卫星的测量值推断的Pm：5浓度，建立和改进大气Pm2.5质量和趋势的全球暴露评估。[方法]结合3个卫星反演的Pm25源数据，得出1998-2012年10km×10km尺度上全球Pm2．5估计值。对每一个源数据，通过GEOS—Chem化学物运输模型把气溶胶光学厚度总柱反演与近地面Pm2.5联系起来，以表示当地的气溶胶光学性能和垂直廓线。从文献中收集210个全球基于地面的Pm2.5观测值，用北美和欧洲之外其他地区的测量值来评估基于卫星的估计值。[结果]1998--2012年，全球人口加权的大气Pm25浓度每年增加0．55gg／m3（95％CI：0．43～0．67）（2．1％／年；95％CI：1．6％-2．6％）。尽管在一些发达地区Pm2.5减少，但在一些发展中地区Pm2．s的增加推动了这一全球性的变化。在东亚，Pmzs水平高于世界卫生组织（WHO）第一个中期目标35μg／m3的人口比例从1998--2000年的51％上升到2010---2012年的70％。相比之下，北美高于WHO空气质量指南10μg/m3的人口比例，从1998--2000年的62％下降到2010---2012年的19％。北美及欧洲以外地区的卫星反演估计值和地面测量值之间存在关联（r=0．81；n=210；斜率=0．68）。卫星反演的估计值偏低，提示真实的全球浓度可能更高。[结论]卫星观测值提供了大气Pm2.5浓度的全球性长期变化的新认识。从这项研究中获得的Pm2.5的卫星反演估计值和地面观测值可供公众使用。

关键词：细颗粒物卫星浓度评估长期暴露观测 Pm2.5 应用

Exceedance Probability of the Standardized Precipitation-Evapotranspiration Index in the Texas High Plains

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Agricultural Sciences 2017年第8期8卷 783-800页

作者： Jerry E. moorhead Gary W. marek Prasanna H. Gowda Thomas H. marek Dana O. Porter Vijay P. Singh David K. brauer Conservation and Production Research Laboratory USDA-ARS Bushland TX USA Grazinglands Research Laboratory USDA-ARS El Reno OK USA Department of Biological and Agricultural Engineering Texas A&M AgriLife Research Amarillo TX USA Department of Biological and Agricultural Engineering Texas A&M AgriLife Research and Extension Service Lubbock TX USA Department of Biological and Agricultural Engineering Texas A&M University College Station TX USA

Drought is a common occurrence in many arid and semi-arid regions that can have large negative impacts on water resources and agricultural production. Since agricultural drought is affected by both water supply and demand (precipitation and evapotranspiration), it is beneficial to include both in agricultural drought monitoring. The Standardized Precipitation-Evapotranspiration Index (SPEI) was found to be a suitable drought index for monitoring agricultural drought. In this study, the SPEI calculated from agro-meteorological weather stations was used to determine exceedance probabilities at five levels in the Texas High Plains. In addition, the kriging method was used to interpolate between the stations to generate spatial maps for the exceedance probabilities. No significant differences were found between stations, indicating any station should be suitable to represent the Texas High Plains. Results showed drought conditions occurred at all five probability levels during the summer growing season for this region. Although differences were not significantly different, the interpolated maps showed a trend where minor differences in the SPEI values were associated with the West-East precipitation gradient. However, there was no trend associated with the North-South air temperature gradient. A risk analysis showed that the SPEI probability values can provide policy and decision makers with additional information for better water management in the Texas High Plains.

关键词： Drought Semi-Arid Region Water management Irrigation

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