共查询到20条相似文献，搜索用时 250 毫秒
1.
在发动机结构不作改动的情况下,进行燃用中比例甲醇汽油M30和M40与93#汽油的动力性、经济性对比试验分析。其结果表明,发动机在中低转速条件下,燃用M30的动力性与燃用93#汽油的动力性几乎相当;而当发动机在高转速条件下,燃用M40的动力性较燃用93#汽油的动力性有所提高。在经济性方面,低转速(2 000 r/min)下,93#汽油的油耗量及油耗率低于M30、M40;在中等转速(3 000 r/min)下,且扭矩小于50N·m时,93#汽油经济性最好,扭矩大于50 N·m时,M30的经济性优于93#汽油及M40甲醇汽油。 相似文献
2.
电喷式汽油发动机掺烧甲醇的试验研究 总被引：4，自引：0，他引：4
以在电喷发动机上应用甲醇汽油的关键技术为研究对象，在应用面最广的电控燃油喷射式汽油机上进行了中等比例掺烧甲醇燃料的试验研究。详细分析了不同组份的甲醇和汽油的混合燃料(M30、M40、M50)的发动机台架性能试验及行车试验，并在动力性、经济性和排放特性上与相同条件下燃用汽油进行对比。 相似文献
3.
基于乙醇汽油和汽油的空燃比的差异以及对发动机性能的影响,在不改变发动机结构参数的情况下,试验研究发动机燃用93号E10和93号汽油的基本性能。从试验可以得出发动机燃用乙醇汽油与汽油的动力性、经济性及排放特性对比。在中、低转速动力性下降,在较高转速动力性相当;燃油经济性在低、中负荷略有下降,在高负荷略好于汽油;在怠速工况下,乙醇汽油会降低汽油机的CO、HC和NOx的排放。针对燃料空燃比对发动机的性能影响,对发动机燃用乙醇汽油的空燃比的控制进行研究。对发动机的喷油器喷孔直径、喷油脉宽及喷油量的定量修正,为发动机燃用乙醇汽油的空燃比控制提供参考。 相似文献
4.
中比例乙醇汽油对电喷发动机性能影响的研究 总被引：1，自引：0，他引：1
介绍了中比例乙醇汽油(E10，E20)与93#汽油的对比试验，并对试验结果进行了分析。实验结果表明，捷达前卫电喷汽油机燃用E10、E20与燃用93#汽油相比，动力性相当，燃油消耗率略有上升，CO、HC、NOx排放大幅降低。 相似文献
5.
通过台架实验对M15、M30和97~#汽油进行考察,主要考察因素包括扭矩、油耗率、输出功率及排放性能(NOx、CH、CO)。结果表明:在同等条件下,醇基燃料比97#汽油的功率、扭矩、能耗略低,但排放性能(NOx、CH、CO)较优,这主要是由于醇基燃料中甲醇热值较低,降低了燃料整体的热能,但是醇基燃料富含氧,后期可以通过助剂的配伍,使得醇基燃料在具有较为优异的排放性能前提下获得较好的动力性能。因此,发展醇基清洁燃料、补充和部分替代石油燃料是缓解我国能源紧张局势、提高资源综合利用、保护生态环境的一条有效捷径。 相似文献
6.
《技术与市场》2001,(3)
汽油是工业、农业、交通运输业、国民经济各部门乃至社会生活不可缺少的重要物资，是各种机动设备特别是汽车的重要燃料。为降低生产成本和车辆燃料消耗费用、提高燃烧效率、减少排放物现介绍一种城市用清洁型汽油及其制备方法。 此种清洁型汽油乃是以国产７０ ＃以上的汽油或石脑油及甲醇为主要原料，添加少量助溶剂、动力性能改进（助燃、清洁）剂，通过调和生产制得。此种清洁型汽油的原料，添加剂的组份和所占比例如下： 汽油或石脑油６０％～９０％，甲醇１０％～３０％，助溶剂１％～８％，动力性能改进剂３％～１０％。 其中，主要的助溶剂为Ｃ３－Ｃ１０醇和Ｃ３－Ｃ１０醚，动力性能改进剂为Ｃ；一Ｃ。含氧烃。原料和添加剂按比例加人静态混合器，在常温下混合均匀即可。 清洁型汽油采用价格较低的石油、化工产品和工业废料为主要原料，可以大大降低生产成本和汽车燃料费用。由于该配方与常规汽油互溶，而且不含铅和卤素添加剂，可以有效减少汽车尾气污染和对发动机的腐蚀。该汽油对汽车性能无不良影响，亦无需对现有车辆进行改造。 联系人；刘伟 地址：辽宁省盘锦市兴隆刍 辽河石油勘探局石油化工所 邮编：１２４０１０城市用清洁型汽油 相似文献
7.
《中南林业科技大学学报(自然科学版)》2015,(4)
为研究高原环境下EGR系统与燃用生物质燃料B25E5对柴油机性能和排放的影响,进行了柴油机台架试验研究。试验结果表明:燃用纯柴油时,外特性工况下的动力性随着EGR率的增大而降低,降低的幅度为3%~15%;负荷特性下,EGR率对柴油机的经济性无明显影响,缸内最高燃烧压力和最高燃烧温度随着EGR率的增大均降低。与纯柴油相比,燃用生物质燃料B25E5时,动力性有所下降,下降的幅度为2%~12%;燃油消耗率有所上升,开启EGR后,经济性最差,最大降幅达到29%;缸内最高燃烧压力和最高燃烧温度变化均不明显。在2 200 r/min的不同负荷工况下,燃用B25E5并开启EGR后,NOx排放量下降,平均下降幅度为35%,碳烟排放有小幅上升,平均增幅为16%,CO的排放量无明显变化。 相似文献
8.
随着我国对城市大气污染的严格控制,现许多城市中的部分公交车和出租车的汽油机已改装成天然气或天然气-汽油双燃料的发动机.在发动机结构不作大改动的情况下,这种天然气发动机虽然排放的有害气体明显减少,但其动力性能下降明显.要同时解决有害气体的排放和发动机性能不能改变这两个问题,只有采用专门设计的天然气发动机. 相似文献
9.
目前,发动机多用汽油、柴油作燃料.用汽油作燃料的称为汽油机,或叫汽化器式发动机;用柴油作燃料的称为柴油机,或叫压燃式发动机.现对两种发动机分析如下. 相似文献
10.
分析甲醇柴油的十六烷值、密度、运动粘度、腐蚀性和馏程等性质。采用数值计算的方法研究不同甲醇掺混比例对混合燃料十六烷值的影响;开展燃料的蒸馏特性试验、粘温特性试验,研究不同甲醇掺混比例（M0、M10、M20）对混合燃料的蒸馏特性、粘温特性的影响,初步探讨柴油中甲醇含量的混合燃料理化参数的影响规律。 相似文献
11.
Caroline Narayan Paulo M. Fernandes Jo van Brusselen Andreas Schuck 《Forest Ecology and Management》2007
The current paper analyses the potential for prescribed burning techniques for mitigating carbon dioxide (CO2) emissions from forest fires and attempts to show quantitatively that it can be a means of achieving a net reduction of carbon emissions in the context of the Kyoto Protocol. The limited number of available studies suggests that significant reductions in CO2 emissions can be obtained and that prescribed burning can be a viable option for mitigating emissions in fire-prone countries. The present analysis shows that the potential reduction attained by prescribed burning as a percentage of the reduction in emissions required by the Kyoto Protocol varies from country to country. Out of the 33 European countries investigated, only in one the requirements of the Kyoto Protocol could potentially be achieved by applying prescribed burning, while three other nations showed a potential net CO2 emissions reduction of about 4–8% of the Kyoto requirements and the majority showed a reduction of less than 2%. This implies that prescribed burning can only make a significant contribution in those countries with high wildland fire occurrence. Over a 5-year period the emissions from wildfires in the European region were estimated to be approximately 11 million tonnes of CO2 per year, while with prescribed burning application this was estimated to be 6 million tonnes, a potential reduction of almost 50%. This means that for countries in the Mediterranean region it may be worthwhile to account for the reduction in emissions obtained when such techniques are applied. 相似文献
12.
13.
Guillermo E. Defossé Gabriel Loguercio Facundo J. Oddi Julio C. Molina P. Daniel Kraus 《Forest Ecology and Management》2011,261(12):2243-2254
Wildland fire is a natural force that has shaped most vegetation types of the world. However, its inappropriate management during the last century has led to more frequent and catastrophic fires. Wildland fires are also recognized as one of the sources of CO2 and other greenhouse gases (GHG) that influence global climate change. As one of the techniques used to reduce the risk of destructive wildfires, prescribed burning has the potential of mitigating carbon emissions, and effectively contributes to the efforts proposed as part of the Clean Development Mechanism within the Kyoto protocol. In order to apply this concept to a real case, a simulation study was conducted in pine afforestation in the Andean region of Patagonia, Argentina, with the objective of evaluating the potential of prescribed burning for reducing GHG emissions. The scenario was established for a ten year period, in which simulated prescribed burning was compared to the traditional management scheme, which included the probability of annual average of wildfire occurrence based on available wildfire statistics. The two contrasting scenarios were: (1) managed afforestation, affected by the annual average rate of wildfires occurred in the same type of afforestation in the region, without prescribed burning, and (2) same as (1) but with the application of simulated prescribed burning. In order to estimate carbon stocks, and CO2 removals and emissions, we followed the guidelines given for GHG inventories on the Agriculture, Forestry and Other Land Uses (AFOLU) sector of the International Panel on Climate Change (IPCC), while the terminology used was the established by IPCC (2003). Data of afforested area, thinnings, and biomass growth were taken from previous surveys in the study area. Downed dead wood and litter (forest fuel load, FFL) was estimated adjusting equations fitted to those fuels, based on field data. Results show that comparing the two scenarios, prescribed burning reduced CO2 emissions by 44% compared to the situation without prescribed burning. The prescribed burning scenario represented about 12% of the total emissions (prescribed burning plus wildfires). Furthermore, avoided wildfires by simulated prescribed burning allowed an additional 78% GHG emissions mitigation due to extra biomass growth. Simulated prescribed burning in commercial afforestation of Patagonia appears to be an effective management practice not only to prevent wildfires, but also an efficient tool to mitigate GHG emissions. However, more studies in different scenarios would be needed to generalize these benefits to other ecosystems. 相似文献
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15.
炼山对杉木人工林群落学特征影响的研究 总被引：3，自引：0，他引：3
The effects of human disturbance on community features of Cunninghamia lanceolata mixed forests were stud-ied, the results showed that 1 ) the proportion of phanerophyes in the not burning forests were larger than in the control burn-ing forests; 2)the species richness in the control burning forests were larger than that in not burning forests, but the speciesdiversity and Simpson evenness in the control burning forests were lower than that in the not burning forests;3)the effect ofcontrol burning on the dominant species in tree and shrub layers of Cunninghamia lanceolata mixed forests were little, buton the herb layer was very large,which dominated by positive plant species; 4)the community structure was more complexwhich would increase the crown density of stand. 相似文献
16.
炼山在华西雨屏区造林时广泛应用,杉木林采伐迹地炼山后的土壤理化性质研究鲜有报道.本文以华西雨屏区28 a生杉木林（对照）及其采伐迹地为研究对象,通过传统的炼山方式后采样测定土壤pH值、全N、P、K及其有效性以及Ca和Mg含量等,旨在阐明炼山对华西雨屏区杉木采伐迹地土壤的理化性质短期效应.结果表明：炼山能显著提高土壤pH值,能显著增加土壤0～40 cm层的全N含量.不同土层的P含量对炼山的响应不同,炼山后表层土（0 ～20 cm）的全K含量呈现先增加后减少的趋势,中层土（20 cm～40 cm）是先下降、后增加,底层土（40 cm～60 cm）持续下降.炼山后土壤中速效N、有效P的含量均先增加、后降低,而速效K的含量先下降,后增加.炼山后的土壤表层Ca含量显著增加,但对土壤中层和底层土的Ca含量影响趋势无规律.土壤各层中的Mg含量在炼山后明显下降. 相似文献
17.
Ciro Abbud Righi Paulo Maurício Lima de Alencastro Graa Carlos Clemente Cerri Brigitte Josefine Feigl Philip Martin Fearnside 《Forest Ecology and Management》2009,258(11):2535-2546
Estimates of greenhouse-gas emissions from deforestation are highly uncertain because of high variability in key parameters and because of the limited number of studies providing field measurements of these parameters. One such parameter is burning efficiency, which determines how much of the original forest's aboveground carbon stock will be released in the burn, as well as how much will later be released by decay and how much will remain as charcoal. In this paper we examined the fate of biomass from a semideciduous tropical forest in the “arc of deforestation,” where clearing activity is concentrated along the southern edge of the Amazon forest. We estimated carbon content, charcoal formation and burning efficiency by direct measurements (cutting and weighing) and by line-intersect sampling (LIS) done along the axis of each plot before and after burning of felled vegetation. The total aboveground dry biomass found here (219.3 Mg ha−1) is lower than the values found in studies that have been done in other parts of the Amazon region. Values for burning efficiency (65%) and charcoal formation (6.0%, or 5.98 Mg C ha−1) were much higher than those found in past studies in tropical areas. The percentage of trunk biomass lost in burning (49%) was substantially higher than has been found in previous studies. This difference may be explained by the concentration of more stems in the smaller diameter classes and the low humidity of the fuel (the dry season was unusually long in 2007, the year of the burn). This study provides the first measurements of forest burning parameters for a group of forest types that is now undergoing rapid deforestation. The burning parameters estimated here indicate substantially higher burning efficiency than has been found in other Amazonian forest types. Quantification of burning efficiency is critical to estimates of trace-gas emissions from deforestation. 相似文献
18.
为了实现地沟油的有效回收利用,采用热裂解和催化酯化工艺制备了地沟油生物燃料油,并把制得的燃料油与0#柴油调合进行台架试验测试。结果表明:通过热裂解反应,油品的物质组成发生了变化,热裂解油主要组分为C10~C18的烷烃、烯烃和羧酸等,其中烃类质量分数占64%。裂解油再经过催化酯化反应,油品的燃料性能进一步提高,所制得的生物燃料油性能如下:酸值0.29 mg/g,黏度2.58 mm2/s,热值为44 MJ/kg,冷凝点-7℃,冷滤点-3℃,各性能都符合国家生物柴油标准。台架试验测试混合燃料的动力性能和排放性能,数据表明地沟油生物燃料油对于柴油机动力性能影响甚微,排放尾气环保性能更优。 相似文献
19.
本文在传统制作工艺的基础上,在生漆与聚合桐油的混合阶段,引入了高速分散搅拌,研磨两种方法,从而使生漆与聚合桐油的偶连更加紧密,分散更加均匀,从而达到干燥时间短,涂层均匀,性能稳定。试验表明：基于生漆与桐油的成本差距巨大的考虑,按照经济性与技术性相统一的原则,认为在春秋季节,生漆与桐油的最佳搭配比例是4∶6,在夏冬季节,生漆与桐油的最佳搭配比例是6∶4。通过涂刷,涂层表面的物理性能漆膜附着力达到国标1级,抗冲击性60～70 cm,涂层表面硬度达到了国标铅笔2 H,表面光泽度120%,柔韧性1.0 mm。进行的耐碱性、耐酸性、耐盐性、97﹟汽油、沸水中进行耐腐蚀性以及在200℃时的耐热性的性能测试,表现良好。 相似文献
20.
Álvaro Enríquez-de-Salamanca 《Journal of Sustainable Forestry》2020,39(4):417-431
ABSTRACTForest fires contribute to climate change mainly due to emission of greenhouse gases by biomass burning and loss of sequestration by sink destruction. The average contribution in Spain between 1998 and 2015 was 9,494,910 Mg CO2 eq per year, 23.8% from biomass burning and 76.2% from loss of carbon sequestration, the latter three times higher than the former, although the emissions from combustion are usually the only accounted. Regarding to the vegetation burned, 43.6% of emissions come from forest (17.7% conifers, 4.8% hardwoods and 21.1% Eucalyptus), 53.7% from scrublands and 2.7% from grasslands. The loss of sequestration is 6.6% in the fire year and by 93.4% in previous years. Scrubland burning produces a greater amount of emissions than forests, but forest regeneration is slower, with greater influence on the loss of sequestration. It is essential a forest management focused on increase fire resilience and adaptation to climate change, increase the effectiveness of extinction works to reduce fire damages and implement actions to recover the burnt vegetation, because the loss of sinks is a critical aspect. 相似文献