TCD燃烧系统对柴油机燃烧和排放性能改善效果的试验研究

为探究道依茨TCD2015柴油机上配备的导流燃烧系统(简称TCD燃烧系统,T表示涡轮增压器,Turbocharger,C表示进气中冷,Charge air cooling,D为柴油颗粒捕集器,Diesel particle filter)对改善柴油机燃烧性能和降低污染物排放的效果,采用单缸机试验对TCD燃烧系统在不同转速、负荷和过量空气系数下的燃烧和排放性能进行研究。试验结果表明不同工况下TCD燃烧系统燃油消耗率和Soot排放量均低于传统ω燃烧系统,燃油消耗率最大降幅为7.01%,Soot排放量最大降幅为86.67%,且低过量空气系数(1.2～1.6)下TCD燃烧系统仍具有较好的性能。为揭示TCD燃烧系统改善油气混合促进燃烧的机理,采用AVL Fire软件建立了柴油机性能仿真模型。计算结果表明,TCD燃烧系统的环状凸起结构将燃油导向内外两室,从而促进了缸内燃油发展过程,燃油当量比大于4的浓混合气区域燃油质量比例相比ω燃烧系统降幅最大为9.75%,活塞下移时TCD燃烧系统内油束撞击浅盘侧壁形成撞壁射流扩大了燃油扩散面积,从而改善了缸内油气混合质量,燃油当量比小于1的均匀混合气区域燃油质量比例相比ω燃烧系统降幅最大为7.45%,因此TCD燃烧系统能够有效改善柴油机的燃烧和排放性能,可应用于柴油机高负荷和低过量空气系数工况综合性能提升。研究结果可为柴油机燃烧系统开发和改进提供参考。     

Growth Responses and Differences in Gene Expression depending on Cultivation Temperature between Alternative type Wheat Varieties

Journal of Crop Science and Biotechnology - Two domestic wheat varieties were grown in the growth chamber set at 17°C, 20°C, 23°C and 26°C on average after the emergence of...     

茶树花青素形成分子机理的研究进展

花青素是由类黄酮合成途径产生的次生代谢产物,含量高时会使茶树新梢呈现红色或紫色。同时,花青素相比儿茶素等具有更明显的抗氧化、预防肿瘤等药理保健作用。文章就茶树花青素合成途径、转录及转录后调控等方面进行综述,以期更好地为高花青素茶树的育种研究提供理论依据。     

菊花新品种‘东篱雅致’

菊花新品种‘东篱雅致’是以中国传统大菊品种‘绿朝云’为母本，以花形奇特、不同色系的‘钟声’，‘清水莲’和‘笑靥’等传统大菊品种作父本进行人工混合授粉，经连续选择育成。舌状花松针形，粉、绿复色。植株低矮, 直立性强, 适于盆栽观赏, 主要观赏期11月中旬—下旬，可以用于北京地区节日布展或庭院观赏。     

The persistence of inter‐regional hierarchy in technology transfer networks: An analysis of Chinese patent licensing data

This paper asks whether the technological development of a nation reduces the inter‐regional hierarchy in knowledge flow. We examine two scenarios that are the alternative to each other. The first is what we call the globalization of regional innovation system/weakening of inter‐regional hierarchy scenario: As many regions develop their niches in the global economy, the national “anchor” region loses its relative importance as the importer and distributor of new knowledge, rendering the domestic inter‐regional hierarchy less significant as a result. The second scenario is the globalization of national innovation system/persistence of inter‐regional hierarchy. The nation’s traditional anchor region becomes even more active in importing technology and distributing it to other regions of the country. To test which scenario is closer to reality, we employ social network metrics to analyse inter‐regional technology diffusion networks using Chinese patent licensing data for the 1998–2013 period. Our findings support the second scenario, showing that the influence of the traditional anchor region persists in the hierarchical network structure as new cities enter the network. We found five anchor regions: the three usual suspects—Beijing, Shanghai and Shenzhen—plus two that were slightly less expected—Dongguan and Suzhou.     

Verification by polymerase chain reaction of vertical transmission of Theileria sergenti in cows

To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases.     

小麦雪霉叶枯病产量损失的初步研究

人工接种试验结果表明,雪腐格氏霉(Gerlachia nivalis)引起的小麦成株期叶枯、鞘枯和穗腐,鞘枯使小麦穗粒重减少2.1％～27.1％,千粒重降低9.5％～16.9％;穗腐使小麦穗粒重减少9.6～33.9％,千粒重降低7.8％～17.9％;鞘枯—穗腐复合症状使穗粒重减少10.2％～55.2％,千粒重下降9.5％～14.8％;叶斑—鞘枯—穗腐使穗粒重减少11.7％～47.1％,千粒重下降12.1％～18.3％。     

德国牧羊犬pose步造型及影像拍摄

德国牧羊犬是世界著名犬种，引入我国已有数十年的历史。虽然大家对德国牧羊犬已有较深入地了解研究，但对于能够凸显德国牧羊犬外貌特征、形体结构及健康状况的pose步造型及影像拍摄方面，尚未有专题介绍，而这确又是饲养、训练德国牧羊犬成就具有直接表征意义的重要体现。     

反硝化聚磷一体化设备中微生物数量变化的研究

对反硝化聚磷除磷脱氮污水处理新工艺运行初期系统中的微生物数量进行了跟踪检测，并对细菌总数，霉菌，放线菌，硝化细菌，亚硝化细菌，反硝化细菌在不同日期的数量变化进行了研究。