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31.
结合工程实际提出一种汽车电子燃油喷射信号模拟系统的设计方法,实现发动机所需相关传感器信号的虚拟设计。该模拟系统通过相关的设备实测出发动机电子燃油喷射系统工作时各参数数据,利用Matlab和V isual Basic软件对所获得的数据进行分析和处理,得出其变化规律及相互关系,并把所得的数据流以通信方式传输给单片机,以便单片机依此产生相关模拟信号并传送给发动机的控制系统。  相似文献   
32.
Taylorella equigenitalis is a gram-negative coccobacillus and the causative agent of a transmissible venereal disease in horses known as contagious equine metritis. Outbreaks of contagious equine metritis have been documented in various countries since 1977, with the most recent discovery in the United States in December 2008. During disease occurrences, culturing semen samples for T equigenitalis before breeding may help to prevent transmission of this disease; however, little is known about the antimicrobial activity of equine semen extenders against the organism. The purpose of this study was to investigate the infectivity levels of T equigenitalis in three equine semen extenders inoculated with known concentrations of the organism. The semen extenders used for this study included INRA 96, E-Z Mixin BF, and VMDZ. In addition, Timentin was added to INRA 96 at three different concentrations (0.5, 1.0, and 1.5 mg/mL) to investigate possible synergistic effects of antibiotic supplementation of extenders. Results were based on the visual counting of the colonies on chocolate Eugon agar plates. Both INRA 96 (with added Timentin) and VMDZ (as supplied by the manufacturer) significantly reduced the numbers of T equigenitalis isolated from semen extenders as compared with INRA 96 (as supplied by the manufacturer) or the antibiotic free E-Z Mixin BF. Our findings indicate that INRA 96 (with added Timentin) or VMDZ may significantly decrease the growth of T equigenitalis in extended semen; however, it is also important to consider the possible effects of antibiotic supplemented extenders on sperm longevity and fertility in addition to eliminating specific pathogens in semen.  相似文献   
33.
The in vitro formation of newly formed adventitious buds and shoots from internodal branch segments was studied on 12-month-old plants of Citrus aurantium L. cv. Brazilian. The effects of 6-Benzyladenine (BA) and α-Naphthalene acetic acid (NAA) treatments were evaluated on adventitious bud and shoot regeneration. High rates of bud initiation and shoot development were obtained both with BA supplemented medium, in the range from 1 mg L−1 to 3 mg L−1, and with 0.1 mg L−1 NAA supplemented medium. NAA concentrations above 1 mg L−1 significantly reduced bud initiation and shoot elongation. The results obtained using different in vitro culture vessels such as Petri dishes, tubes and glass culture jars were compared. The highest adventitious bud induction was observed in Petri dishes for internodes cultured in 2 mg L−1 BA supplemented medium, with 95% responsive explants forming 9.0 ± 2.4 adventitious buds. The adventitious buds observed in Petri dishes reached a maximum height of 1 mm, with no further development, while some of the adventitious shoots cultured in tubes and glass culture jars grew over 1 cm in height. A shoot regeneration gradient of the internodes collected along the branch axis was noticed, with basal ones exhibiting higher regeneration frequency.  相似文献   
34.
AIM: To study the effects of basic fibroblast growth factor (bFGF) on neuronal apoptosis and fractalkine expression in ischemic penumbra after cerebral ischemia/reperfusion in rats.METHODS: Thirty-six rats were randomly divided into 3 groups: sham operation group, ischemia/reperfusion group and bFGF group. The model of middle cerebral artery occlusion was established by the method of intraluminal filament blockage. The middle cerebral arteries were blocked for 1 h and then reperfused for 24 h. Neurological performances of all rats were scored with Bederson's standard. The brain tissues of the rats were stained and the average infarct volume was calculated. TUNEL method was used to determine the number of apoptotic neurons, and the expression of fractalkine was detected by the method of immunohistochemistry.RESULTS: The score of neurological performances in bFGF group was 2.23±0.59, lower than that in ischemia/reperfusion group (3.18±0.65). The number of apoptotic neurons in bFGF group (13.22±1.35) was lower than that in ischemia/reperfusion group (17.28±1.01, P<0.05), which was the lowest in sham operation group (0.91±0.65). Compared with sham operation group, the expression of fractalkine in ischemia/reperfusion group was decreased. The expression of fractalkine in bFGF group was mainly higher than that in ischemia/reperfusion group (P<0.05).CONCLUSION: Up-regulation of fractalkine may be one of the molecular mechanisms of bFGF to protect neurons against ischemia/reperfusion injury.  相似文献   
35.
李凤琴 《安徽农业科学》2008,36(13):5676-5677
结合学术期刊的版式特点,阐述了学术期刊版式设计应遵循的基本原则:内容与形式和谐统一;层次清晰,节奏分明;比例协调,对称有度;静动相宜,虚实互补,强调了版式设计中应注重人本主义因素。  相似文献   
36.
张洁  王敏 《安徽农业科学》2008,36(4):1710-1711
在对西部农村代课教师存在基础进行客观分析的前提下,提出解决西部农村代课教师问题的相关建议。  相似文献   
37.
当今农村,贵州农村整体贫困,大人对孩子的学习总体期望值较低,将孩子的学业定位在完成九年义务教育,将孩子的前途定位在外出打工上。加之监护人年龄大,文盲比例高,教育管理上弊端较多.学校是学生生活学习的主要场所,班主任在学校管理中,扮演一个非常重要的角色,本文对农村基础教育中的班主任工作进行了探讨。  相似文献   
38.
通过对科技创新和成果转化状况的分析,认为基层农业科技单位是中国农业科技创新和科技成果转化的重要力量;但基层农业科技单位面临规模小负担重,资金不足人才匮乏,竞争能力不强等诸多问题。面对这一现状,基层农业科技单位唯有积极探索机制改革,强化科技创新,加速成果转化才能得以生存、发展和壮大。  相似文献   
39.
在土地管理信息系统中,编制直观、清晰的三维地质图是开发人员所必须具备的基本能力.就如何利用VB来开发三维地质构造图的基本步骤进行了详细地介绍,其中对像素格式的设定以及光照和材质的设置进行了详细的描述.  相似文献   
40.
彭璐 《安徽农业科学》2009,37(5):2258-2259
归纳总结了公众参与城市绿地建设的发展趋势,立足城市绿地建设各个阶段的特点,解析公众参与城市绿地建设的基本模式,指出公众参与是未来城市绿地建设研究的重要内容及发展方向。  相似文献   
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