脉冲电晕等离子体活化纯CO2的反应

研究了在常温常压下，脉冲电晕等离子体对温室气体CO2的活化与转化分别考察了反应气体流速、脉冲电压峰值、放电频率对纯CO2转化的影响．结果表明，CO2主要分解为CO和O2，另有少量积碳和臭氧产生；随着反应气体流速的增加，CO2转化率、CO产率和选择性降低；随着脉冲电压峰值和放电频率的升高，CO2转化率、CO产率增大，CO选择性降低．     

高能等离子体分解CO_2气体研究

为治理温室气体ＣＯ_２，本工作在低温常压条件下，利用超高压脉冲电晕放电产生的高能量（２０～５０ｅＶ）非平衡等离子体作用于ＣＯ_２气体分子，使ＣＯ_２分子化学结合键断裂，在定向化学反应作用下，将ＣＯ_２气体分解成单原子气体分子Ｏ_２和单质固体微粒Ｃ。ＣＯ_２分解率在９０％以上。     

Current status of applying microwave-associated catalysis for the degradation of organics in aqueous phase – A review

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Thriving on challenge stressors? Exploring time pressure and learning demands as antecedents of thriving at work

In the conceptualization of thriving at work, it is emphasized that employees' learning and vitality are two equally important components of thriving and that thriving is facilitated by contextual features and available resources. In this study, we examined the effects of two challenge stressors (time pressure and learning demands) on thriving at work. Based on the literature on challenge and hindrance stressors, we proposed that challenge stressors positively affect learning and negatively affect vitality. To uncover underlying mechanisms, we measured challenge appraisal and hindrance appraisal of work situations in a diary study. A sample of 124 knowledge workers responded to three daily surveys (before the lunch break, during the afternoon, and at the end of the workday) for a period of five workdays. Results indicate that the indirect effects of learning demands and time pressure on learning are mediated by challenge appraisal, whereas indirect effects of learning demands on vitality are mediated by hindrance appraisal. Overall, our study shows that challenge stressors have a positive total effect on learning but no total effect on vitality. These differential relationships call for a finer distinction between the two components of thriving at work in future research. Copyright © 2016 The Authors Journal of Organizational Behavior Published by John Wiley & Sons Ltd.     

被保护层双重卸压特性研究

为探索复合煤层群保护层开采时在双重卸压条件下被保护层的不同卸压特性,采用物理相似模拟试验和计算机数值模拟来研究其双重卸压规律。对比分析被保护层的膨胀率和卸压率后发现:在双重卸压条件下,被保护层的膨胀变形呈现"M"形态,膨胀率在不同时空下表现出叠加特性;另外,煤岩体的弹性势能因受首采保护层的影响而释放,被保护层卸压率表现出卸压区域边缘不连续而卸压程度和范围均增加的特点。最后,现场测试计算得到被保护层的透气性系数,其变化规律证实双重卸压效果明显。     

The effects of component dimensions on heat transfer and pressure loss in shell and tube heat exchangers

In this study, the effects of geometric properties such as baffle spacing, baffle cut, sealing strips, gaps between heat exchanger components, number of tubes and tube passes have been investigated for shell and tube heat exchangers (STHE). For this purpose, geometrical dimensions and data of a specific heat exchanger (HE) used in an industrial application have been obtained. The HTRI Xchanger Suite Educational software was utilized to analyze the reference HE, to verify the results of the software and the output temperatures of the fluids, the shell side heat transfer coefficient (HTC) and the pressure loss (PL) values were compared with the experimental data. After confirming that the results of the software were within the acceptable deviation values, the geometric dimensions of the reference design were changed and new analyzes were carried out to examine the effects of several dimension options on the performance of STHE. Results were discussed in a detailed and comprehensive manner via curves.     

模拟高低空交变环境下30CrMnSiNi2A钢力学性能研究

目的研究30CrMnSiNi2A钢制腔体的力学性能影响及演化规律。方法借助高低温低气压试验和中性盐雾试验交替进行,模拟高低空交替变化的腐蚀环境。通过比较静力拉伸试验和疲劳试验的结果,进一步揭示预腐蚀对静力拉伸性能和疲劳性能的影响。结果经过预腐蚀处理,30CrMnSiNi2A钢制腔体的力学抗拉强度下降了0.73%,规定塑延伸强度上升了0.04%,断后伸长率下降了0.95%。疲劳寿命数据与对数疲劳寿命数据均符合正态分布,未发生明显变化。结论高低空交变环境下,腔体内部会发生一定程度的腐蚀,但由于腐蚀程度较小,对30CrMnSiNi2A钢力学性能影响不大。     

多因素综合高原高寒气候环境模拟加速试验箱研制

目的研制一种多因素综合高原高寒气候环境模拟加速试验箱,主要用于高原地区使用的工艺、材料和零部件的快速筛选和环境适应性评价。方法通过高原气候特征分析、工艺验证和文献分析,进行设计、制造、试验谱设计和试验验证等工作。结果解决了光照和高低温低气压环境条件的同时施加问题,形成同时施加光照、气压、温度、湿度和风速五因素的高原高寒气候环境模拟加速试验箱。设计了一套高原高寒气候环境模拟加速试验谱,实现了高原高寒气候环境的多因素综合模拟和加速。结论试验箱各项技术指标达到设计要求。塑料样品的拉伸强度和冲击韧性性能、有机涂层的色差和光泽变化指标,与拉萨站试验结果进行对比,具有良好相关性和加速性。本试验箱可用于高原地区使用的工艺、材料和零部件的快速筛选和环境适应性快速评价。     

螺纹接头处拉应力作用下的缝隙腐蚀行为

目的 研究N80钢在高温高压中缝隙和应力耦合作用下的腐蚀行为,为油井管的选材和螺纹选型提供参考。方法 以油管螺纹接头为研究对象,在高温高压釜模拟地层环境,采用电化学方法和表面分析技术,研究N80钢在缝隙单因素作用下和缝隙-应力耦合作用下的腐蚀行为。结果 仅有缝隙作用24 h后,缝内存在大量腐蚀产物堆积,缝外几乎没有腐蚀产物。40 ℃时的凹槽深度为17.2 μm,而70 ℃时的凹槽深度则达到82.7 μm。在缝隙和应力耦合作用24 h后,在缝隙口处发现有腐蚀产物堆积,缝隙内腐蚀程度比缝隙外腐蚀程度更为严重。40 ℃时,弹性形变试样的缝隙口处凹槽深度约为35.3 μm,塑性形变的试样缝隙口处凹槽深度约为41.3 μm;而70 ℃时,发生弹性变形和塑性变形的试样缝隙口处凹槽深度则分别为143.7 μm和243.9 μm。结论 缝隙和应力耦合作用使缝隙口处凹槽的深度加深,且深度随着腐蚀时间和温度的增加而增大,塑性形变时凹槽深度最大。这表明应力的施加会加剧N80钢的缝隙腐蚀,导致形成更深的腐蚀凹槽,这反过来又会导致应力的进一步集中,应力腐蚀风险增加。因此,缝隙和应力对N80钢在高温高压地层水环境中的腐蚀具有协同作用。     

海洋水下滑翔机浮力调节系统的设计与实验

目的提高海洋滑翔机浮力调节系统的可靠性,进一步降低系统功耗,设计气压与液压结合的低功耗浮力调节系统。方法基于理论分析确定系统的体积控制量,设计气压调节模块以保证高压油泵的正常工作与回油的顺利进行。利用有限元方法分析承压管路的可靠性,通过实验测试,验证浮力系统的响应性能。结果浮力系统的排油效率随着外压的增大而减小,2MPa的压力会使出油率降低3%左右,同时功耗增加50%左右。在大气压力环境下,依靠系统内负压,400 s即可完成回油600 mL,完成上浮到下潜的转换。结论设计的浮力调节系统的气压调节装置能以较低的功耗保障主泵的正常工作,同时保障回油过程的通畅,满足海洋滑翔机对浮力调节的要求,可以应用于一般海洋深度的水下滑翔机。