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61.
褐煤作燃料热电厂产生的循环流化床脱硫灰应用于我公司2 500 t/d新型干法窑生产线水泥生产,由于褐煤中全硫含量偏高且波动大,由此致使脱硫过程中脱硫剂比例变化波动也大,将熟料、矿渣、脱硫灰分别用小磨粉磨后进行试验,在试验基础上,除了对该脱硫灰超细粉磨外,同时必须要解决脱硫灰的均化和f-CaO消解问题,通过技术改造使系统设备、工艺更加适合采用脱硫灰复掺技术。 相似文献
62.
采用水热法制备双钙钛矿催化剂Sr_2FeNiO_6,考察不同浓度KOH溶液(4 mol·L~(-1)、6 mol·L~(-1)、8 mol·L~(-1)、10 mol·L~(-1)、12 mol·L~(-1)、14 mol·L~(-1))对催化剂性能的影响,利用X射线衍射、比表面积测定、程序升温还原和扫描电镜等对样品进行性能表征,并以催化甲烷燃烧为目标,考察催化剂催化性能。结果表明,矿化剂KOH浓度对样品性能影响较大,当浓度为10 mol·L~(-1)时,起燃温度最低,T_(10%)为430℃;浓度为8 mol·L~(-1)时,样品比表面积最大,为19.0 m~2·g~(-1),完全燃烧温度最低,T_(90%)为610℃。 相似文献
63.
64.
Multimedia Tools and Applications - Understanding human emotions through facial expressions is key enabling technology for interactive robots. Most approaches of facial expression recognition are... 相似文献
65.
采用累积叠轧焊+中间退火法复合轧制1060Al/Fe基非晶多层铝合金复合板材。利用光学显微镜、扫描电镜、X-衍射分析仪以及拉伸试验机分析Al基复合材料的微观组织结构变化、断口形貌、物相组成以及力学性能。结果表明:Fe基非晶复合材料的增强体在300 ℃中间退火过程中发生部分晶化,在累积变形轧制过程中发生破碎,并随着变形道次的增加,破碎程度随之增大;复合板前6道次的累积轧制变形出现了明显的加工软化现象,并且随着变形道次的增加,其加工软化的效果愈明显;随着累积轧制变形道次增加,Al基复合材料的力学性能发生了明显的变化,第2道次轧制变形后屈服强度与抗拉强度达到了最大值为140 MPa和156 MPa,伸长率为5.53%,达到最佳综合性能。 相似文献
66.
A wind generator equipped with hydraulic energy storage (WG‐HES) uses hydraulic transmission systems instead of gearbox transmissions, thus eliminating high‐power converters and reducing the tower‐top cabin weight. When there is no wind or the wind speed is extremely low, the pressured oil released by accumulators is used to drive a motor to operate at a constant speed, thereby generating constant‐frequency power. However, few studies have examined the constant speed control characteristics for generating electricity using only an accumulator group. In this study, a combined constant speed (CCS) proportional–integral–derivative (PID) control method based on “variable displacement and throttling” is proposed, which includes two closed loops and one regulating loop. First, a simulation model of the CCS PID control method for a variable motor was established in the Simcenter Amesim program. The influence of different PID parameters on the anti‐interference ability of the constant speed control of the motor was analyzed under a given load step. Then, we obtained the range of control parameter values and a set of optimal values. Second, the effectiveness of the CCS control method and the accuracy of the simulation results were verified on a 600‐kW WG‐HES system prototype. The results verified that the CCS control method has good anti‐interference ability and can meet the requirements of constant speed control for a variable motor under the best PID parameters. These results can provide a basis for developing control strategies for WG‐HESs when there is no wind or at low wind speeds. 相似文献
67.
68.
针对红阳二矿12号煤层遗煤氧化的规律与特点,有效地进行防灭火工作,掌握采空区中遗煤氧化的速度,对红阳二矿12号煤层进行了煤样升温氧化实验,在温度不断升高的过程中检测出CO与多种烯烃气体,并且在不同温度下煤体析出气体的速度不同,最终选择CO、C2H4、C2H2作为标志性气体,产生的临界温度分别为59、176、403 ℃。在采空区检测出CO气体,说明采空区遗煤进入快速氧化阶段;检测出C2H4气体时,遗煤进入剧烈氧化状态;检测出C2H2气体时,说明采空区中已经产生明火,井下人员需要迅速撤离。通过煤体标志性气体的确定,建立12号煤层自燃预警系统,保证井下工作人员的生命安全与能源的充分利用。 相似文献
69.
Xuefang Luo Ziyang Hou Tianliang Zhou Rong-Jun Xie 《Journal of the American Ceramic Society》2020,103(2):1018-1026
Mn4+-activated fluoride red-emitting narrow-band phosphors have been successfully used in wide color-gamut white LEDs for liquid crystal display (LCD) backlights. However, highly concentrated and toxic HF is usually used in their synthesis, causing environment and safety issues. In this work, we proposed a HF-free green method, that is, using NH4F/HCl instead of HF, to synthesize a series of A2XF6:Mn4+ (A = K, Na, Rb, Cs; X = Si, Ge, Ti) phosphors. The microstructure, photoluminescence (PL) properties, thermal quenching, and applications of the synthesized phosphors were investigated. Using the proposed approach, the phosphors generally showed a pure phase, a particle size ranging from 5 to 45 μm, and some characteristic sharp emission lines of Mn4+ in the red spectral range. The internal quantum efficiency was varied in a broad range of 69%-94% under the 460 nm excitation, depending on the composition of the fluoride host. Among these compositions, K2XF6:Mn4+ (X = Ge and Ti) phosphors even had a similar external quantum efficiency (>60%) with commercial ones. By combining K2GeF6:Mn4+ (narrow-band red) and β-sialon:Eu2+ (narrow-band green) with a blue LED, a white light-emitting diode (wLED) backlight with a color gamut of 87.7% National Television System Committee Standard, color temperature of 8423 K, and a luminous efficacy of 110.8 lm/W was demonstrated. These results indicate that the synthetic method proposed in this work is universal for preparing highly efficient fluoride phosphors used in wLEDs. 相似文献
70.
We previously explored a series of CO2 adducts from alkylated polyethylenimines with C4 to C16 alkyl side chains, serving as climate-friendly blowing agents for polyurethanes (PUs). Among them, the polyethylenimine with C8 alkyl (2-ethylhexyl) side chains demonstrated the highest foaming efficiency. In this study, we further changed the grafting rate of the C8 alkyl, from 7 to 16%, and investigated the effects of the resulting blowing agents on the foaming process. For both foaming systems containing a castor oil-derived polyol (Polycin T-400) or a poly(propylene glycol) polyol (Polyether 4110), the CO2 adducts with a grafting rate of 13% displayed the best foaming performance in terms of high dispersibility in the foaming systems, homogenous cellular morphology, and good mechanical properties. Moreover, the 13%-C8-alkylated blowing agent demonstrated high suitability for the foaming systems from biomass-sourced polyols (like Polycin T-400). Therefore, the optimized CO2-adduct blowing agent could replace the currently used climate-changing hydrochlorofluorocarbons and hydrofluorocarbons, as well as might contribute to the development of future renewable PU foams. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48752. 相似文献