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针对安徽华谊化工公司气化炉灰水系统生产运行中存在的结垢问题,分析了不同位置灰垢的物理化学性质、主要成分及形成灰垢的灰水成分。根据不同位置的灰水结垢现象,推断出不同位置的结垢机理,据此采取:增加分散剂加药点、调整工艺操作、降低系统氨氮含量、定期射流清洗等处理措施,起到了良好的阻垢效果。 相似文献
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针对D校菜鸟驿站存在的布局不合理、拥堵严重、排队混乱以及取件效率低等问题进行优化.通过5 W1 H分析方法对其进行改进分析提问,取得站内各个因素之间的联系,后基于调整型SLP方法将其重新布局功能区以及作业区,重新设置货架位置及摆放方法,并结合目视管理方法将其货架标识完善,添加路线指示标识.经优化改善后站点可增加3个同类货架,1个4.5 m2的大件摆放区以及1个1 m2的退货寄件存放区.最后基于ECRS方法得到客户取件移动距离优化率为10.6%,取件时间优化率达30.05%. 相似文献
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Tongling Xia Yue Qi Xilei Dai Jinyu Liu Can Xiao Ruoyu You Dayi Lai Junjie Liu Chun Chen 《Indoor air》2021,31(6):2020-2032
To evaluate the separate impacts on human health and establish effective control strategies, it is crucial to estimate the contribution of outdoor infiltration and indoor emission to indoor PM2.5 in buildings. This study used an algorithm to automatically estimate the long-term time-resolved indoor PM2.5 of outdoor and indoor origin in real apartments with natural ventilation. The inputs for the algorithm were only the time-resolved indoor/outdoor PM2.5 concentrations and occupants’ window actions, which were easily obtained from the low-cost sensors. This study first applied the algorithm in an apartment in Tianjin, China. The indoor/outdoor contribution to the gross indoor exposure and time-resolved infiltration factor were automatically estimated using the algorithm. The influence of outdoor PM2.5 data source and algorithm parameters on the estimated results was analyzed. The algorithm was then applied in four other apartments located in Chongqing, Shenyang, Xi'an, and Urumqi to further demonstrate its feasibility. The results provided indirect evidence, such as the plausible explanations for seasonal and spatial variation, to partially support the success of the algorithm used in real apartments. Through the analysis, this study also identified several further development directions to facilitate the practical applications of the algorithm, such as robust long-term outdoor PM2.5 monitoring using low-cost light-scattering sensors. 相似文献
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In this work,we developed a simple strategy to synthesize a carbon material with high nitrogen and rich carbon defects.Our approach polymerized diaminopyridine(DAP) and ammonium persulfate(APS).Following a range of different temperature pyrolysis approaches,the resulting rough surface was shown to exhibit edge defects due to N-doping on graphite carbon.A series of catalysts were evaluated using a variety of characterization techniques and tested for catalytic performance.The catalytic performance of the N-doped carbon material enhanced alongside an increment in carbon defects.The NC-800 catalyst exhibited outstanding catalytic activity and stability in acetylene hydrochlorination(C_2 H_2 GHSV=30 h~(-1),at 220℃,the acetylene conversion rate was 98%),with its stability reaching up to 450 h.Due to NC-800 having a nitrogen content of up to 13.46%,it had the largest specific surface area and a high defect amount,as well as strong C_2 H_2 and HCl adsorption.NC-800 has excellent catalytic activity and stability to reflect its unlimited potential as a carbon material. 相似文献
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Baohua Zhang Dejian Dai Jichao Huang 《Critical reviews in food science and nutrition》2018,58(12):2099-2118
Over the past decades, imaging and spectroscopy techniques have been rapidly developing and widely applied in nondestructive fruit and vegetable quality assessment. The physical properties (including size, shape, color, position, and temperature) and biological properties (including cultivar, season, maturity level and geographical origin) of fruits and vegetables vary from one to another. A great variety of physical and biological properties of agricultural products influence the optical propagation properties and interaction behaviors with incident light, thus decreasing the quality inspection accuracy. Many attempts have been made in image correction and spectral compensation methods to improve the inspection accuracy. This paper gives a detailed summary about influence of physical and biological variability, as well as the correction and compensation methods for eliminating or reducing the effects in fruit and vegetable quality nondestructive inspection by using imaging and spectroscopy techniques. The advantages and disadvantages of the solution methods are discussed and summarized. Additionally, the future challenges and potential trends are also reported. 相似文献
70.
分析了淬火配分处理对锻态Fe-0.2C-9Mn-3.5Al钢显微组织及力学行为的影响。结果表明,热处理态试验钢主要由块状δ-铁素体、马氏体和板条状残留奥氏体等多相构成;残留奥氏体的体积分数随等温淬火温度升高而增大,在310 ℃时达到峰值;310 ℃等温淬火后在400 ℃配分3 min时可以获得较优的综合力学性能,抗拉强度和断后伸长率分别为1175 MPa和21.50%,强塑积达到25.26 GPa·%;应力-应变曲线中存在着明显的“锯齿”状起伏,可能与亚稳态的残留奥氏体集中转变为马氏体有关。 相似文献