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21.
针铁矿是分布广泛、储量丰富的铁氧化物,其主要成分为α-羟基氧化铁(α-FeOOH)。为了探究针铁矿在催化H2O2烟气脱硝反应中的性能,本文通过沉淀-水解法制备了α-FeOOH,并在自行搭建的实验台上开展了α-FeOOH催化H2O2的低温烟气脱硝实验研究,深入分析了H2O2流量、H2O2浓度、汽化温度、反应温度和共存气体浓度等工况参数对脱硝性能的影响。采用离子色谱(IC)分析了单独脱硝反应和同时脱硫脱硝反应后的含氧酸成分,结合各项表征分析技术考察了催化剂反应前后的理化特性和稳定性。实验结果显示,随着汽化温度和反应温度的升高,NO的脱除效率先增加后降低;增加H2O2浓度对脱硝效率有明显的促进作用。当汽化温度为140℃、反应温度为160℃时,以2.5mL/h注入10mol/L的H2O2脱硝效率达到80%。当SO2浓度为1000μL/L时,脱硝效率提高至86.4%。离子色谱分析结果显示,单独脱硝反应和同时脱硫脱硝反应后含氧酸产物为HNO3和H2SO4。反应前后催化剂的表征结果显示,α-FeOOH在脱硝反应后依然具有良好的稳定性,显示出针铁矿在低温烟气脱硝工艺中的潜在应用前景。 相似文献
22.
针对输煤暗道的生产工艺现状,提出了采用通风与密闭抽尘净化技术,结合转载落料点密闭干雾降尘等技术措施,实现了输煤暗道内粉尘的的综合治理,通过粉尘浓度在线监测系统进行智能化控制,实现对输煤暗道通风除尘系统的远程连续监测监控,输煤暗道转载点下风侧5 m作业人员通行的位置总粉尘浓度由380.8 mg/m3降至19.8 mg/m3,降尘效率达94.8%,呼吸性粉尘浓度从96.7 mg/m3降至8.4 mg/m3,降尘效率达91.3%,降尘效果较好,有效地解决了输煤暗道及其转载落料点的粉尘污染问题,为输煤暗道内的粉尘防治提供参考依据。 相似文献
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Yongsen Wei 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(24):3009-3018
Heat transfer has considerable applications in different industries such as designing of heat exchanger, nuclear reactor cooling, control system for spacecraft, and designing of microelectronics cooling. As the surfaces of two metals contact each other, this issue becomes so crucial. Thermal contact resistance (TCR) is one of the key physical parameters in heat transfer of mentioned surfaces. Measuring the experimental value of TCR in laboratory is highly expensive and difficult. As an alternative, numerical modeling methods could be engaged. In this study, inverse problem method solution is utilized as a proper method for estimation of TCR value. In this order, three different configurations (flat-flat, flat-cylinder, and cylinder-cylinder) were utilized in two steady and unsteady state conditions to predict the value of TCR. A comparison between the measured values and obtained values from the simulation show the errors for flat-flat, flat-cylinder, and cylinder-cylinder configuration after 10 min from starting the experiment are 4.6074%, 0.1662%, and 0.5622%, respectively. And in steady-state condition, the corresponding errors are 6.06e-3%, 1.506%, and 0.846%, respectively. In conclusion, the final results establish the fact that the inverse problem method solution can predict TCR values between contacting surfaces. 相似文献
25.
为进一步提高联合循环效率,参考现有燃气蒸汽联合循环12.5 MPa/568℃亚临界蒸汽参数,提出27 MPa/585℃超临界蒸汽参数,根据燃气蒸汽联合循环计算模型,以397 MW燃气轮机联合循环机组为例,计算了超临界蒸汽参数与两种亚临界蒸汽参数的底循环效率和联合循环效率,并分析对比了3种蒸汽参数的底循环效率对联合循环效率的贡献。研究表明:对于同一燃气轮机,超临界和亚临界中低压蒸汽参数不同时,超临界蒸汽参数的底循环效率比亚临界提高了4.3%,蒸汽底循环输出功率占联合循环机组输出功率的百分比由30.21%增加到32.62%,联合循环净效率增加了2.21%,联合循环机组的输出功率增加了20.38 MW;中低压蒸汽参数相同时,超临界蒸汽参数的底循环效率比亚临界提高了2.87%,蒸汽底循环输出功率占联合循环机组输出功率的百分比由31.16%增加到32.62%,联合循环净效率增加了1.44%,联合循环机组的输出功率增加12.5 MW。 相似文献
26.
Outcome‐based ventilation: A framework for assessing performance,health, and energy impacts to inform office building ventilation decisions 下载免费PDF全文
This article presents an outcome‐based ventilation (OBV) framework, which combines competing ventilation impacts into a monetized loss function ($/occ/h) used to inform ventilation rate decisions. The OBV framework, developed for U.S. offices, considers six outcomes of increasing ventilation: profitable outcomes realized from improvements in occupant work performance and sick leave absenteeism; health outcomes from occupant exposure to outdoor fine particles and ozone; and energy outcomes from electricity and natural gas usage. We used the literature to set low, medium, and high reference values for OBV loss function parameters, and evaluated the framework and outcome‐based ventilation rates using a simulated U.S. office stock dataset and a case study in New York City. With parameters for all outcomes set at medium values derived from literature‐based central estimates, higher ventilation rates’ profitable benefits dominated negative health and energy impacts, and the OBV framework suggested ventilation should be ≥45 L/s/occ, much higher than the baseline ~8.5 L/s/occ rate prescribed by ASHRAE 62.1. Only when combining very low parameter estimates for profitable impacts with very high ones for health and energy impacts were all outcomes on the same order. Even then, however, outcome‐based ventilation rates were often twice the baseline rate or more. 相似文献
27.
Deploy Efficiency Driven k-Barrier Construction Scheme Based on Target Circle in Directional Sensor Network 下载免费PDF全文
Fan Xing-Gang Che Zhi-Cong Hu Feng-Dan Liu Tao Xu Jin-Shan Zhou Xiao-Long 《计算机科学技术学报》2020,35(3):647-664
Journal of Computer Science and Technology - With the increasing demand for security, building strong barrier coverage in directional sensor networks is important for effectively detecting... 相似文献
28.
《工程(英文)》2020,6(12):1395-1402
In this report, we show that hyperspectral high-resolution photoluminescence mapping is a powerful tool for the selection and optimization of the laser ablation processes used for the patterning interconnections of subcells on Cu(Inx,Ga1−x)Se2 (CIGS) modules. In this way, we show that in-depth monitoring of material degradation in the vicinity of the ablation region and the identification of the underlying mechanisms can be accomplished. Specifically, by analyzing the standard P1 patterning line ablated before the CIGS deposition, we reveal an anomalous emission-quenching effect that follows the edge of the molybdenum groove underneath. We further rationalize the origins of this effect by comparing the topography of the P1 edge through a scanning electron microscope (SEM) cross-section, where a reduction of the photoemission cannot be explained by a thickness variation. We also investigate the laser-induced damage on P1 patterning lines performed after the deposition of CIGS. We then document, for the first time, the existence of a short-range damaged area, which is independent of the application of an optical aperture on the laser path. Our findings pave the way for a better understanding of P1-induced power losses and introduce new insights into the improvement of current strategies for industry-relevant module interconnection schemes. 相似文献
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30.
Meimei Xia Jian Chen Xiao‐Jun Zeng 《International Transactions in Operational Research》2020,27(2):1080-1100
Existing approaches to data envelopment analysis focus mainly on the derivation of the efficiency of the individual decision‐making unit (DMU) or on the calculation of the weights of multiple inputs or outputs, but pay little attention to the team interest of all the DMUs. Motivated by the idea of team reasoning, in which the benefit of the team is of higher importance than that of each individual, this paper considers all the DMUs as a team and introduces the team indexes including the overall efficiencies, variance, boundaries of all the DMUs, and relationships between DMUs. Several models are first developed to estimate values of the team indexes based on which decision makers can provide their preferences regarding them. Then, models are established to obtain the interval efficiencies of individual DMUs under the condition that the team indexes are satisfied. Several examples are given to illustrate the proposed approaches and verify their applicability. 相似文献