电控发动机故障实验台的开发     

蔡伟义  郑燕萍  李贵炎 《林业机械与木工设备》2002,30(5):8-11

介绍了电控发动机微机控制系统故障实验台的组成和分类，阐述了实验台电路特征，整理制作过程以及实验台显示板，实验台控制系统工作原理，结构特征，设计制作方法。  相似文献   

Molecular cloning and tissue distribution of a short form chicken leptin receptor mRNA     

Liu X  Dunn IC  Sharp PJ  Boswell T 《Domestic animal endocrinology》2007,32(3):155-166

In mammals, alternative splicing of the leptin receptor (LEPR) produces several C-terminal truncated isoforms that are believed to play a role in the transport, cellular internalisation and degradation of the hormone leptin. The chicken leptin receptor (chLEPR) is similar to its mammalian counterparts in terms of its intron/exon structure and conserved motifs. However, it is unknown whether the chLEPR also undergoes alternative splicing. To test this, structural analysis of intron 19 of the chLEPR, equivalent to the intron in which alternative splicing occurs in mammals, was combined with 3'-rapid amplification of cDNA ends (3'-RACE) to search for chLEPR splice variants. A 44-amino acid alternative exon 20 was identified that is spliced to generate a short isoform of the chLEPR (chLEPR-SF). Comparative sequence analysis of intron 19 identified two regions that are highly conserved between the chicken and mammals, indicating their possible importance as intronic elements in the regulation of alternative splicing of the LEPR in vertebrates. Tissue expression of the chLEPR-SF was lower and more restricted than that of the chLEPR long isoform. Collectively these data demonstrate that the chLEPR is alternatively spliced to produce at least one short isoform, as is the case in mammals.  相似文献   

发展绿色、健康宠物经济的途径探索     

朱院利 《湖南农机》2007,(7):114-116

经济的发展和人们消费观念的改变,催生了各种经济形式,宠物经济就是其中之一。本文分析了宠物经济快速发展的原因和现状,阐述了宠物经济发展所带来的隐患,并对发展绿色、健康宠物经济的途径进行了探索。最终探讨规避不利因素,促进绿色、健康宠物经济的发展。  相似文献   

汽车催化转化器劣化因素分析及故障诊断     

高照亮 《农机化研究》2005,(4):257-260

随着我国汽车排放法规的不断加严,催化转化器被广泛应用。由于催化转化器在我国应用的时间较短,故有关它的正确使用方法、故障诊断资料及经验较缺乏。为此,分析研究了催化转化器劣化机理,总结正确使用方法和故障诊断经验,旨在通过提高对发动机使用、保养和维护的水平,充分发挥催化器的作用,达到真正减少废气排放的目的。  相似文献   

基于最大疑似度概率统计的不确定性网上故障诊断   总被引：1，自引：0，他引：1  

辛惠娟  钱东平  张少轩  赵睿明 《农机化研究》2007,(2):207-209

针对汽车发动机异响类故障是故障诊断的难点,应用"基于最大疑似度的概率统计"法对汽车发动机的异响类不确定性故障进行了推理诊断,并用更新知识库的方法实现了对电脑常见故障现象的故障诊断,推理结果与实际情况基本一致,证明"基于最大疑似度的概率统计"法应用于不确定性故障诊断科学有效.  相似文献   

21世纪头十年徐州市鸟类种群变化     

田勇燕  周虹 《安徽农业科学》2013,(36):13911-13913

对徐州市1999年和2012年间鸟的种类和数量变化进行了分析.两次调查结果表明,总的种数变化不大,但种的组成变化较大,两次调查中均出现的种仅占总种数的50％左右.  相似文献   

成都港两侧秋季鸟类资源调查     

张腾  刘丹  黄明远  文陇英 《安徽农业科学》2014,(33):11734-11737

2013年9月至2013年11月,采用样线法对乐山市五通桥区冠英镇和牛华镇的鸟类资源进行了调查.共记录到冠英镇鸟类28种,隶属5目17科.牛华镇共记录到鸟类35种,隶属6目19科.多样性分析表明,冠英镇农田生境多样性指数最高（2.645）,牛华镇水域生境均匀度指数最高（0.949）,2个镇的水域生境之间的相似性最低（0.476）.冠英镇水域生境鸟类群落不稳定,对岷江河应采取一定的保护措施.  相似文献   

鸟类的语言   总被引：1，自引：0，他引：1  

买买提  阿依古丽 《干旱区研究》1998,15(4):33-36

正如人类的语言活动一样，发声是自然界中动物进行种群及个体识别，信息交流的重要工 具。它在动物生存竞争中具有极为重要的意义。鸟类利用发声进行种间的识别、求偶、觅食、报警、筑巢等活动。鸣声中包含有丰富的生物学信息，而被称为鸟类的语言，鸟类鸣叫是其种祖特征之一。鸟类的鸣叫和鸣唱依赖于发育完善的鸣管并接受脑各级发声中枢组成的机能控制系统的调控。在鸣禽脑中还存在着鸣唱学习通路。  相似文献   

汽车起动机常见故障检查诊断及修理     

肖扬 《黑龙江八一农垦大学学报》1998,10(1):53-57

汽车起动机是用来起动机的装置，它主要由三部分组成，即电机、传动机构和起动开发、本文介绍了汽车起动机常见故障的检查诊断步骤，并提出了具体修理方法。  相似文献   

Seed removal by ants,birds and rodents in a woodland savanna habitat in Zimbabwe     

《African Zoology》2013,48(2):295-299

Seed removal from bait stations was studied in miombo habitat in western Zimbabwe. Previous studies of seed predation in southern Africa have largely been conducted in desert ecosystems. However, this woodland-savanna habitat is more mesic and has relatively predictable rainfall patterns. The experiment was conducted in grassy and woody microhabitats in the hot, dry season and early wet season, and followed a year in which precipitation was 69 % of the long-term average. Birds removed the greatest quantity of seeds, followed by ants and then rodents. Previous studies in northern hemisphere mesic environments emphasize the importance of rodents and minor role of invertebrates in seed predation. Although our site appears to have more in common with southern hemisphere desert sites than with northern hemisphere mesic sites, we recognize that our results are likely to reflect a lower limit of consumption by rodents.  相似文献