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991.
Energy conversion analysis of vehicle electromagnetic suspension using power flow method 总被引:1,自引:0,他引:1 下载免费PDF全文
The energy regenerative characteristic of vehicle electromagnetic suspension is analyzed based on the power flow. In order to solve the key problem of energy quantification of electromagnetic suspension,a calculation and analysis method of energy conversion efficiency is proposed. A comparative work between the active system,passive system and the maximal output power system is made through computer simulation. It is demonstrated that in the aspect of vehicle dynamics,the active system is superior to the passive system. In the aspect of energy regenerative ability,the passive system is superior to the active system. And the energy regenerated by the active system is more than the consumed energy. So the active system has the ability of powering itself. 相似文献
992.
通过环青海湖地区草甸羊粪添加控制试验,研究不同用量羊粪(S0,S1和S2分别为0,0.34,0.56 kg·m-2)对该草甸群落结构和生产力、生物多样性及土壤含水量的影响。结果表明:S1与S0,S2与S0,S1与S2间的植物群落高度存在显著差异(P<0.05),植被平均盖度差异不显著;除籽蒿(Artemisia sphaerocephala)外,各处理对研究地区的主要物种高度均存在显著差异(P<0.05);各处理间植株重要值差异不显著;除了豆科地上生物量和地上总生物量各处理间无显著差异,其他主要物种地上生物量几乎都存在显著差异(P<0.05);各处理间群落丰富度指数变化不显著,群落均匀度指数为 S0高于S1和S2, S0与S1存在显著差异(P<0.05);对于物种多样性指数,S1和S2均低于S0,S0与S2差异不明显,且S0与S1及S1与S2存在极显著差异(P<0.01)。施肥对0~15 cm表层土壤含水量的影响较为明显,对15~30 cm土壤含水量影响不大。 相似文献
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There are a series of city environmental problems especially in the mountain city along with the city fast development. In recent decade, many scholars have studied the urban heat island, the urban temperature, the urban wind field, the precipitation and the urban visibility etc. But the urban thermal environment has not been settled radically. All the measures have not been used in the practice. And the researches in thermal environment of the mountain cities are very few. So the authors consider Chongqing as the researching object. Chongqing is one of the typical mountain cities in the semi-tropical. Sequentially we find out the characteristic of the thermal environment in the mountain city. Further the authors seek for the measures to plan and build ecological city. They conclude that CFD can be used in the simulation of urban environment, and use the result of simulation in urban planning is possible. The thermal environment in the center of Chongqing needs to be improved. 相似文献
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997.
采用RT-PCR结合RACE技术,扩增得到全长为2265bp的莲藕"美人红"品种的GBSS基因的cDNA序列(GenBank登录号EU938541),其中开放阅读框(ORF)长为1848bp,共编码615个氨基酸。用DNAman软件比对,莲藕GBSS基因cDNA与金鱼草(AJ006293)、马铃薯(EU403426)、大豆(EF153101)、水稻(EU735072)Wx基因cDNA序列的同源性分别达61.2%、59.6%、64.2%、50.6%。对该基因编码的氨基酸序列进行Blastp分析发现,该序列与金鱼草的序列同源性最高,达到77%,与马铃薯、甘薯的同源性达到75%,与豆科植物的同源性在70%~75%,与禾本科植物的同源性在65%~70%。 相似文献
998.
AIM: The goal of this study was to compare different methods for tumor antigen preparation, to observe the induction of tumor-specific cytotoxic T lymphocytes in rats by dendritic cells (DCs) pulsed with different tumor antigens. METHODS: The precursors of dendritic cells were isolated from bone marrow of rats, stimulated in vitro with recombinent rat granulocyte-macrophage colony-stimulating factor (rrGM-CSF) and interleukin-4 (rrIL-4). Then rat DCs were pulsed with C6 tumor cell antigens prepared with different methods: freeze-thaw, boiling or total protein extracted from ultrasonic crushed tumor cell. Subsequently primed DCs were cocultured with T lymphocytes isolated from spleen to induce CTL. Lymphocyte chemoattractant factor from DCs and cytokine IFN-γ release were determined by ELISA, the cytotoxicity of CTL was assayed by JAM test. RESULTS: DCs pulsed with boiled tumor cell in vitro induced an enhanced ability of T-cell proliferation and cytotoxic T lymphocyte activity.CONCLUSION: Our results demonstrated that DCs primed with boiled tumor cell may represent a method for inducing immune responses against the entire repertoire of tumor antigens of malignancies. 相似文献
999.
详细报道了虫蜀敌的形态特征和生物学特性。虫蜀敌Armacustos(Fabricius)属半翅目蝽科。该虫在吉林省一年发生1代,以成虫越冬。成虫取食鞘翅目幼虫和卵 相似文献
1000.
鱼肉酶解物及壳聚糖对鲤鱼涂膜保鲜效果的研究 总被引:1,自引:0,他引:1
以感官评分、挥发性盐基氮、菌落总数、K值为指标,研究比较了鱼肉酶解物和壳聚糖为原料的涂膜液对鲤(Cyprinus carpio)(4℃)冷藏过程中品质变化的影响.结果显示:贮藏期间,对照组的感官评分显著低于各涂膜组(P<0.05).贮藏前8d,涂膜组能够显著抑制K值的升高(P<0.05).鱼肉酶解物和壳聚糖涂膜组均能够显著抑制细菌的生长,而贮藏2~6d内鱼肉酶解物涂膜鲤鱼的菌落总数显著低于壳聚糖涂膜组(P<0.05).贮藏后期,鱼肉酶解物组能延缓TVB-N值的升高,壳聚糖涂膜组能够显著抑制TVB-N值的升高(P<0.05).鱼肉酶解物可作为一种新的可食性涂膜材料,用于延长鲤鱼的贮藏期. 相似文献