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71.
介绍了微型燃气轮机(微燃机)冷热电三联产系统(三联产)的构成,利用热力学理论对三联产系统在额定工况下的产品成本单价进行了分析,计算了在不同天然气成本单价和微燃机不同工况下排气(烟气)余热利用率ηy的发电量成本单价和制冷量成本单价。计算表明,发电量成本单价随ηy的增加而减小;天然气成本单价增加会增大发电量成本单价;提高ηy对降低发电量成本单价有作用;制冷量成本单价随天然气成本单价增加而增加;ηy在70%后对单位制冷量成本单价的影响降低。 相似文献
72.
用于浮法玻璃冷端设备的包装必须能够保护设备,在储藏、运输及中转过程中不受损坏。以越南900t/d生产线为例,介绍了出口冷端设备的包装设计。 相似文献
73.
气体水合物是一种新型空调蓄冷介质,但由于诱导期长、过冷度大和生长缓慢的问题限制了其工程应用。本文采用均相成核方法,研究促进剂对水合物增长期内的生长速率的影响。实验研究无促进剂和添加了质量浓度为0.1%的十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(SDBS)、四丁基溴化铵(TBAB)、四氢呋喃(THF)和全氟烷基醚醇铵盐型阴离子Intechem-01(FC-01)的样品在3℃下HCFC-141b水合物增长期内的生长情况。结果表明:在水合物增长期内,热力学促进剂TBAB、THF对水合物生长速率提高作用较小,而动力学促进剂表面活性剂SDS、SDBS和FC-01明显提高生长速率,其中FC-01效果最佳;分析表面活性剂混合液的液滴尺寸,FC-01对HCFC-141b的分散及稳定性最好,液滴平均尺寸稳定在约350 nm,这也说明对客体材料分散及稳定性优异的动力学促进剂能显著提高水合物增长期内生长速率。 相似文献
74.
Dimitrios Raptis Jesper Kjeldskov Mikael B. Skov 《Behaviour & Information Technology》2017,36(4):333-350
Recently a number of studies appeared that operationalised coolness and explored its relation to digital products. Literature suggests that perceived coolness is another factor of user experience, and this adds to an existing explosion of dimensions related to aesthetics, hedonic quality, pragmatic quality, attractiveness, etc. A critical challenge highlighted in prior research is to study the relationships among those factors and so far, no studies have empirically examined the relationship between coolness and other established user experience factors. In this paper, we address this challenge by presenting two studies one that focuses on factors from two cool questionnaires, and one that compares them against existing User eXperience (UX) factors. Our findings show that factors from the two cool questionnaires converge and they also converge to existing, established UX factors. Thus, 11 distinct cool and UX factors converge into 5 for the case of mobile devices. Our findings are important for researchers, as we demonstrate through a validated model that coolness is part of UX research, as well as for practitioners, by developing a questionnaire that can reliably measure both perceived inner and outer coolness as well as the overall coolness judgement based on 5 factors and 21 items. 相似文献
75.
采用浓缩消解、冷原子吸收的方法,测定水中的痕量汞,通过多次实验,测定方法的准确性和精密度都较高,说明该方法可行。 相似文献
76.
Gold, platinum and tungsten films were deposited by low energy input (7 mA, 450 V), or high deposition rate (80 mA, 1500 V), diode sputter coating and by ion beam sputter coating. Film structures on Formvar coated grids and on the surface of coated erythrocytes, resin embedded, sectioned, and recorded at high magnification in a TEM were compared using computer-assisted measurements and analysis of film thickness and grain size. The average grain size of the thinnest gold and platinum films was relatively independent of the mode or rate of deposition but as the film thickness increased, significant differences in grain size and film structure were observed. Thick platinum or gold films deposited by low energy input sputter coating contained large grain size and electron transparent cracks; however, more even films with narrower cracks but larger grain size were produced at high deposition rates. Ion beam sputter coated gold had relatively large grain size in 10 nm thick films, but beyond this thickness the grains coalesced to form a continuous film. Platinum films deposited by ion beam sputter coating were even and free of electron transparent cracks and had a very small grain size (1–2 nm), which was relatively independent of the film thickness. Tungsten deposition either by low energy input or ion beam sputter coating resulted in fine grained even films which were free of electron transparent cracks. Such films remained granular in substructure and had a grain size of about 1 nm which was relatively independent of film thickness. Tungsten films produced at high deposition rates were of poorer quality. We conclude that thick diode sputter coated platinum and gold films are best deposited at high deposition rates provided the specimens are not heat sensitive, the improvement in film structure being more significant than the slight increase in grain size. Thick diode or ion beam sputter coated gold films should be suitable for low resolution SEM, and thin discontinuous gold films for medium resolution SEM. Diode sputter coated platinum should be suitable for medium resolution SEM and ion beam sputter coated platinum for medium and some high resolution SEM. 1–5 nm thick tungsten films, deposited by low energy input or ion beam sputter coating should be suitable for high resolution SEM, particularly where contrast is of less importance than resolution. 相似文献
77.
对一种具有全面肤质提升作用的长效气垫粉凝霜进行了功效评价。在广州地区选择21名25~40岁具有彩妆使用习惯的女性,在产品使用前和使用后12 h对皮肤水分、肤色、光泽度、毛孔状况及细纹深度和数量进行了分析;同时考察了使用产品后皮肤表面温度变化情况并就满意度对受试者进行了问卷调查。结果表明,该产品能显著提高肌肤水分,改善肤色,细化毛孔和皮肤纹理,实现较好的遮盖效果并保持长效妆容,并可通过降低皮肤表面温度来提供良好的清凉感。多于85%的受试者对该产品的整体效果表示满意,专业的临床评价也显示该产品安全性高,无受试者出现不良反应。 相似文献
78.
水蓄冷技术是实现电网削峰填谷的重要方式。本文通过影剧院水蓄冷系统的设计和经济技术分析,认为应用水蓄冷系统不仅减少初投资,而且大幅降低运行费用,具有很好的推广价值。 相似文献
79.
对受压翼缘无约束的冷弯薄壁钢梁的屈曲性能进行了有限元分析,将有限元计算结果与不同国家的规范和直接强度法进行了对比分析,验证了有限元程序的有效性,并对现有设计方法进行了修正,修正后的公式可用于受压翼缘无约束的冷弯薄壁型钢的极限承载力的计算。 相似文献
80.
结合国情,稳步建设蓄冷空调工程——关于现阶段在我国发展蓄冷空调的几个认识与策略问题的探讨 总被引:6,自引:1,他引:6
分析探讨了蓄冷空调的国内背景、移峰潜力、经济和社会意义、发展阶段和特点、我国的起步点、经济性与风险、关于示范试点工程、经济鼓励政策等问题,提出了结合国情、稳步发展的若干建议。 相似文献