不同折流板结构螺旋折流板换热器传热性能的比较(英文)

Numerical simulations were performed on flow and heat transfer performances of heat exchangers having six helical baffles of different baffle shapes and assembly configurations, i.e., two trisection baffle schemes, two quadrant baffle schemes, and two continuous helical baffle schemes. The temperature contour or the pressure contour and velocity contour plots with superimposed velocity vectors on meridian, transverse and unfolded concentric hexagonal slices are presented to obtain a full angular view. For the six helix baffled heat exchangers, the different patterns of the single vortex secondary flow and the shortcut leakage flow were depicted as wel as the heat transfer properties were compared. The results show that the optimum scheme among the six configurations is a circumferential overlap trisection helix baffled heat exchanger with a baffle incline angle of 20° (20°TCO) scheme with an anti-shortcut baffle structure, which exhibits the second highest pressure dropΔpo, the highest overal heat transfer coefficient K, shel-side heat transfer coefficient ho and shel-side average comprehensive index ho/Δpo.     

冷轧平整机机前甩尾轧制工艺的开发与应用

本文介绍了柳钢冷轧板带厂1550 mm单机架平整机机前甩尾轧制的工艺。改进前轧制每卷钢卷生产效率低,钢卷成材率低,改进后生产效率、成材率明显提高,部分规格的钢卷能实现带尾剪切长度为零。     

陕南山地烟田不同植烟年限土壤养分的变化

为给陕南山地烟草生产布局及有针对性的施肥措施提供依据,分析了陕南山地烟田不同植烟年限(0~15年)与土壤养分含量的关系。结果表明:随着植烟年限延长,有机质线性下降,全氮和速效钾显著上升,有效磷先上升后下降;氯、有效铁、有效锰、有效硼和有效铜无显著变化或变化很小,有效锌则在第1年急剧下降,之后保持稳定,10年后再次显著下降。认为陕南山地烟区烟叶生产中应适当增加有机肥的施用而合理控制氮肥、磷肥和钾肥的施用,并要注意锌肥的补充。     

澳门融入粤港澳大湾区世界机场群路向研究

粤港澳大湾区世界城市群与世界机场群相伴而生、联动发展.建设世界级机场群，需要5大机场错位发展和良性互动.澳门国际机场是澳门融入粤港澳大湾区重要一极，但机场发展存在与澳门定位、香港珠海空域空运矛盾、澳门土地和环境现状等相关的问题.因此，澳门国际机场今后发展需在葡语国家航线、珠澳密切合作、公务机产业方面努力实现跨越式发展.然而，澳门国际机场改扩建问题争议不断，本文就原址扩建、填海区新建、飞地黄茅岛新建3种模式进行比较分析，探索符合澳门长远利益之方案.     

Collective reflection strategy for moderating conformity tendency and promoting reflective judgment performance

Reflective judgement is crucial for medical-related practitioners in dealing with controversial issues. However, the conformity phenomenon is likely to occur and interfere with reflective judgement learning during interactive activities. Effective strategies are required to moderate the conformity behaviour tendency (CBT) and improve reflective judgement performance (RJP). This study demonstrates two significant results: (a) Compared with the guided self-reflection learning strategy, the online collective reflection (OCR) learning strategy effectively weakened the learners' general CBT while dealing with professional controversial issues; and (b) a significantly negative correlation between the RJP achieved and the change of CBT in online environment was detected in the OCR group. The implications and potential applications in higher education were discussed. Further studies are needed to confirm the long-term effects and the extending application to other professional studies.     

300M超高强钢在中性盐雾环境中的腐蚀行为及机制

摘要：为了研究300M超高强钢在中性盐雾环境中的腐蚀行为及腐蚀机制，采用失重法，宏观、微观腐蚀形貌分析，三维表面轮廓分析及电化学分析的研究方法，来表征腐蚀实验现象并进行分析。结果表明：300M超高强钢在中性盐雾环境中的腐蚀产物为FeOOH、Fe2O3、Fe(OH)3和Fe3O4；腐蚀速率随着腐蚀时间逐渐降低，腐蚀后期（72h）腐蚀速率降低50%；腐蚀初期以点蚀为主，点蚀坑通过横向扩展，逐渐发展为后期的均匀腐蚀，腐蚀表面形貌呈沟壑状；外腐蚀层对基体的保护能力很弱，Cr元素在锈层靠近基体的一侧偏聚使内腐蚀层具有一定的抗腐蚀性。     

Flotation Behavior,Collector Adsorption Mechanism of Quartz and Feldspar-Quartz Systems Using PEA as a Novel Green Collector

Silicon - A novel green cationic surfactant Poly (propylene glycol) bis (2-aminopropyl ether) (PEA) with multiple amine groups was utilized as a collector for flotation separation of quartz from...