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An electrically heated microgroove vaporizer was proposed. The vaporizer mainly comprised an outer tube, an inner tube and an electrical heater cartridge. Microgrooves were fabricated on the external surface of the inner tube by micro-cutting method, which formed the flow passage for fluid between the external surface of the inner tube and the internal surface of the outer tube. Experiments related to the temperature rise response of water and the thermal conversion efficiency of vaporizer were done to estimate the influences of microgroove's direction, feed flow rate and input voltage on the performances of the vaporizer. The results indicate that the microgroove's direction dominates the vaporizer performance at a lower input voltage. The longitudinal microgroove vaporizer exhibits the best performances for the temperature rise response of water and thermal conversion efficiency of vaporizer. For a moderate input voltage, the microgroove's direction and the feed flow rate of water together govern the vaporizer performances. The input voltage becomes the key influencing factor when the vaporizer works at a high input voltage, resulting in the similar performances of longitudinal, oblique and latitudinal microgroove vaporizers. 相似文献
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Due to 4f electron characteristics and alternation valence, cerium involved in an oxidation-reduction reaction in plant, closely relating to photosynthesis. Our studies proved that cerium could promote photosynthesis and greatly improve spinach growth. However, the mechanism of promoting energy transfer and conversion by cerium remains unclear. Here we reported that the effects of Ce^3+ on energy transfer and oxygen evolution in photosystem Ⅱ (PS Ⅱ ) isolated from spinach, which was related to 4f electron characteristics and alternation valence in Ce molecule. The methods of absorption spectrum, fluorescence spectrum were used in the research. Results showed that Ce^3+ treatment at low concentration could suitably change PS Ⅱ mieroenvironment, increase the absorbance of visible light, improve the energy transfer among amino acids within PS Ⅱ protein-pigment complex, and accelerate energy transport from tyrosine residue to chlorophyll a. In summary, the photochemical activity of PS Ⅱ (fluorescence quantum yield) and its oxygen evolving rate were enhanced by Ce^3+. 相似文献
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受地基不均匀下沉影响,中国石油抚顺石化分公司石油一厂油库车间部分贮罐出人口管线存在应力,而该应力的存在将导致管线拉裂、油品跑损,威胁安全生产。简要叙述了运用安全系统工程解决油库罐区因地基下沉而造成的储罐出入口管线存在的应力问题,及金属软管连接在石油一厂储罐中的应用。 相似文献
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提出了一种适合我国一些行业对环境可视化监控需求的数字化远程网络视频监控系统。分析了各子系统(现场监控系统,传输系统,监控中心和计算机网络系统)的结构。介绍了系统结构、计算机网络系统及吉林市电信局多媒体远程网络环境监控系统。系统对100多公里以内的30个分局的机房、营业所进行监控,视频传输大于25帧/秒,图像质量达到MPEG1标准。 相似文献
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为了研究金属材料在疲劳载荷下的温度变化,采用红外热像系统对高周疲劳载荷下6061-T6铝合金的温度演化进行分析,用热像图对疲劳裂纹尖端的塑性区进行测量.结果显示,疲劳加载作用下,循环次数达到107次时6061-T6铝合金试样表面温度的变化分为四个阶段:初始温升阶段、温度缓降阶段、温度二次缓慢上升阶段和温度快速上升阶段.结合热弹性理论、铝合金塑性变形的微观机制分析并预测疲劳载荷下温度的演化和宏观裂纹扩展时裂纹尖端塑性区域大小.宏观裂纹开始扩展时,裂纹尖端的塑性区域可达3.6 mm2,红外热像仪测得结果为3.46 mm2,测试结果与理论结果吻合. 相似文献
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Linolenic acid has great effects on the structure and function of chloroplast. The function of Ce^3+ on the improvement of chloroplast photoreduction activity and oxygen evolution damaged by linolenic acid in spinach by in vitro investigation was studied. Results showed that adding Ce^3+ to the linolenic acid treated chloroplast could greatly decrease the reduction linolenic acid exerted on the whole chain electron transport rate and the photoreduction activity of photosystem Ⅱ (PSII) and photosystem Ⅰ (PSI) as well as the oxygen evolution rate of chloroplast. It indicated that Ce^3+ had the ability to relieve the inhibition of the photochemical reaction of chloroplast caused by linolenic acid to some extent. 相似文献
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采用红外热像法测量AZ31B镁合金板材在疲劳过程中表面温度场的变化,结果表明,当疲劳载荷大于疲劳强度时,镁合金试样表面的温度变化经历5个阶段:温度上升阶段、温度下降阶段、稳定阶段、断裂前的温升阶段和断裂后温度下降阶段。通过疲劳过程中镁合金试样表面的温度变化规律,基于不同的理论提出了2种预测疲劳寿命的方法:由试验过程中试样表面温升(?TM)特征确定其疲劳寿命,?TM–Nf曲线拟合结果表明,?TM=3.89℃为温升极限值,即?TM>3.89℃时,试样会发生断裂,与实测疲劳试样的温升值(3.68℃)相比,误差为5.7%;利用能量法提出了镁合金疲劳寿命的计算公式,用能量法和传统试验方法分别绘制S-N曲线,结果具有很好的一致性,用2种方法分别计算了循环次数为1×107时的疲劳强度ΔσeΦ=99.3 MPa、ΔσeSN=99.8 MPa,误差为0.5%。采用红外热像法估算疲劳寿命具有简单、省时等优势。 相似文献
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