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31.
原油加热炉在变工况下运行会严重降低效率.以加热炉反平衡热效率为基础,通过进行变工况校核热力计算,用偏差分析法推导出加热炉排烟热损失预测模型.该预测模型定量分析了排烟温度、过量空气系数对热效率的综合影响,可帮助现场操作人员对变工况运行的结果进行提前预测,准确找出造成能量损失的部位,并合理调整运行参数,实现加热炉的安全、经济运行. 相似文献
32.
本文通过对高层民用建筑防、排烟设计中一些问题的分析,提出了作者的看法以及采取的具体措施。 相似文献
33.
本文论述了在执行GB50067-91《汽车库修车库、停车库设计防火规范》的基础上,设计地下车库排风排烟、进风系统时应注意的几个问题。 相似文献
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35.
分析了龙血树的生态特征,从龙血树的繁殖方法、化学成分及药理研究、总RNA提取方法、血竭以及龙血树资源的利用与保护几个方面进行了探讨。 相似文献
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38.
多环芳烃在茶树鲜叶及绿茶加工过程中残留水平研究 总被引:1,自引:0,他引:1
利用气相色谱-串联质谱联用仪监测了茶树鲜叶及其绿茶加工中多环芳烃(PAHs)的残留水平。结果表明,不同地区茶树一芽二叶样品PAHs含量差异明显,产地环境PAHs污染程度对茶鲜叶PAHs含量影响较大。茶芽、嫩叶、老叶PAHs含量分别在40.5~52.8μg·kg~(-1)、50.0~67.4μg·kg~(-1)和91.5~97.6μg·kg~(-1)之间,PAHs含量大小顺序为老叶嫩叶芽。汽车尾气对交通公路旁茶树芽和嫩叶PAHs含量影响较大,且对50 m范围内茶树鲜叶影响更明显。电加热干燥模式下,水分散失和PAHs挥发是影响绿茶加工过程中PAHs含量的两个关键因子。加工环节过后,茶叶PAHs含量由61.0μg·kg~(-1)上升到166.1μg·kg~(-1)。摊放和干燥过程中PAHs大量挥发,造成茶叶干重中PAHs残留量由292.0μg·kg~(-1)降低到171.9μg·kg~(-1)。 相似文献
39.
Evaluation of Commercial‐scale Approaches for Cryopreservation of White Crappie,Pomoxis annularis,Sperm
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Charlie M. Culpepper III Amy M. Guitreau Shay Allred Terrence R. Tiersch Peter J. Allen 《Journal of the World Aquaculture Society》2018,49(4):725-734
Crappie, Pomoxis spp., are popular game fish throughout North America and are produced by public and private hatcheries. However, production is limited by a lack of information on tank culture and induced spawning methods. Development of techniques for storage of sperm and in vitro fertilization would increase flexibility in spawning. Therefore, techniques for sperm cryopreservation were examined in white crappie, Pomoxis annularis. Sperm from adult wild white crappie were used to evaluate sperm extender, cryoprotectant agent and concentration, and cooling technique based on post‐thaw sperm motility. Percent egg fertilization was also compared between sperm stored in the two best cryopreservation protocols and two different osmotic activator solutions. Sperm were cryopreserved using treatment combinations of two extenders (350 mOsmol/kg Hanks' balanced salt solution [HBSS] and 350 mOsmol/kg Ca2+free HBSS) and two cryoprotectants (dimethyl sulfoxide [DMSO] and methanol) at concentrations of 5, 10, and 15% that were cooled at four different rates: 5, 10, 20, and 40 C/min. Post‐thaw sperm motility and fertilization rates indicated white crappie sperm can be cryopreserved using either extender, cryoprotectants of either 5% DMSO or 10% methanol, and cooling at 40 C/min. A follow‐up experiment demonstrated sperm in suspensions on ice retained viability after overnight transport. 相似文献
40.
To assess the effect of human interferon-alpha (IFNα) on shipping fever of Thoroughbred
racehorses subjected to long-distance transportation, an IFNα preparation was orally
administered to 48 horses three times (once daily, 3 successive days) before
transportation (IFNα group). In the control group (25 horses), maltose was administered in
the same way. These treatments induced no abnormal findings in Thoroughbred racehorses
before transportation. Immediately after transportation, significant increases in rectal
temperature were observed in both treatment groups, whereas the rectal temperature of the
IFNα group tended to be lower than that of the control group. Although WBC, Fbg, and SAA
immediately after transportation were significantly increased due to transportation in
both groups, the extent of the increases in the IFNα group was significantly smaller than
in the control group. Long-distance transportation had a relatively profound impact on
Thoroughbred racehorses, which was mitigated by IFNα treatment. 相似文献