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111.
Faraz Montazersadgh Hao Zhang Anas Alkayal Benjamin Buckley Ben W.Kolosz Bing Xu Jin Xuan 《Frontiers of Chemical Science and Engineering》2021,15(1):208-219
Utilizing CO2 in an electro-chemical process and synthesizing value-added chemicals are amongst the few viable and scalable pathways in carbon capture and utilization technologies.CO2 electro-reduction is also counted as one of the main options entailing less fossil fuel consumption and as a future electrical energy storage strategy.The current study aims at developing a new electrochemical platform to produce low-carbon e-biofuel through multifunctional electrosynthesis and integrated co-valorisation of biomass feedstocks with captured CO2.In this approach,CO2 is reduced at the cathode to produce drop-in fuels(e.g.,methanol)while value-added chemicals(e.g.,selective oxidation of alcohols,aldehydes,carboxylic acids and amines/amides)are produced at the anode.In this work,a numerical model of a continuous-flow design considering various anodic and cathodic reactions was built to determine the most techno-economically feasible configurations from the aspects of energy efficiency,environment impact and economical values.The reactor design was then optimized via parametric analysis. 相似文献
112.
Ling Tan Kipkorir Peter Jing Ren Baoyang Du Xiaojie Hao Yufei Zhao Yu-Fei Song 《Frontiers of Chemical Science and Engineering》2021,15(1):99-108
The rational design of photocatalyst that can effectively reduce CO2 under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch reaction.In this work,we synthesized a series of CeO2-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO2 reduction.It was found that the selectivity and productivity of CO and H2 from photoreduction of CO2 in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H2 ratio can be widely tunable from 1/7.7 to 1/1.3.Furthermore,compared with LDH,Ce-0.15 also drove photocatalytic CO2 to syngas under 600 nm irradiation.It implied that an optimum amount of CeO2 modifying LDH promoted the photoreduction of CO2 to syngas.This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation. 相似文献
113.
Zhihong Xu Tao Jiang Hao Zhang Yujun Zhao Xinbin Ma Shengping Wang 《Frontiers of Chemical Science and Engineering》2021,15(3):698
Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na+ and MgO on the structure and CO2 adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5-1.5 mm exhibited an excellent capacity for CO2 adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm3∙mol−1) to CaCO3 (36.9 cm3∙mol−1) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO2 capture capacity (9.49 mmol∙g−1), average adsorption rate (0.32 mmol∙g−1∙min−1) and conversion rate of CaO (74.83%) after 30 cycles. 相似文献
114.
以深度学习为代表的人工智能技术不断发展,正逐步渗透并融入电力系统等传统领域.为增强潮流仿真中人机交互的智能化程度,减少仿真技术人员在输入数据、计算分析等过程中的重复劳动,本文从语音识别理论和工程应用相结合的角度开展研究,提出了一种在潮流仿真中嵌入语音识别技术的方法.首先,对现有潮流仿真软件融入语音识别技术的可行性进行了探讨;其次,利用基于开源的电力系统分析工具Pandapower,设计了潮流仿真的语音识别流程,提出了相应的实现方法;最后,在建立的语音识别系统上,对1个仿真算例进行了测试.测试结果表明,本文提出在潮流仿真中嵌入语音识别技术的方法,能有效地实现潮流数据的语音编辑以及潮流计算的语音控制等功能. 相似文献
115.
Wenlu Song Rui Huang Hao Guo Chunguang Yin Chuanling Wang Jun Cheng Weijuan Yang 《中国化学工程学报》2021,37(9):114-120
Steam pretreatment was employed to disrupt microalgal cells for lipids extraction.Effects of steam pre-treatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM) and transmission electron microscopy (TEM).Effect of treatment on lipid extraction was also stud-ied.Microalgal cell walls were distorted after steam pretreatment due to the hydrolysis of organic macro-molecules contained in cell wall.Maximum curvature was increased from 1.88 × 10-6 m-1 to 1.43 × 10-7 m-1 after treatment with the steam at 130 ℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pre-treatment time was increased to 60 min.Increased steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130 ℃ and pretreatment time of 60 min.Lipid extracted from wet microalgal was signif-icantly increased (2.1-fold) after pretreatment. 相似文献
116.
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118.
针对目前难以直接测量运行电缆导体温度的问题,将10 kV三芯电缆热路简化为只含一个等效热容和一个等效热阻的暂态热路,利用一阶热路的响应实现电缆实时导体温度的解析计算;同时,在试验场进行了阶跃电流试验和周期负荷载流量试验,测量电缆导体温度和外皮温度.根据测量的电缆外皮温度和加载的负荷电流计算出试验电缆的实时导体温度,对比发现导体温度的实时计算值与测量值吻合度较高,验证了该计算方法的正确性.该解析计算方法易于实现、计算准确,不仅可用于计算常用敷设方式下不同回路三芯电缆实时导体温度,还可根据电缆当前运行状态适当调整负荷电流,在保证安全的前提下提高现有电缆线路的输电能力. 相似文献
119.
为实现多固废协同利用、降低充填成本,在矿渣基全粒级细尾砂胶结充填料基础上,以流动性和抗压强度为表征,利用热闷钢渣磁选尾渣(钢尾渣)替代部分矿渣作为胶凝材料,脱硫灰和水泥熟料替代部分专用添加剂作为外加剂,采用正交试验探寻掺量规律,优化固体填充料配比,开发钢尾渣-矿渣基软性矿山充填料,并研究了外加剂与胶材比、灰砂比等因素的影响。对比分析了矿渣基准组、钢尾渣-矿渣基准组(B1)、强度最优外加剂组分钢尾渣-矿渣组(B7)等3组充填料的微观形貌及XRD图谱以探究其水化机理。结果表明,钢尾渣替代矿渣量增加、外加剂与胶材比减小,充填料浆流动性改善,但充填体抗压强度下降。强度正交试验结果表明,钢尾渣掺量大小决定强度低高,脱硫灰掺量宜高于水泥熟料。进一步调整外加剂组分配比,在灰砂比为1∶6、钢尾渣替代矿渣为20%条件下,找出B7组外加剂组分为脱硫灰、水泥熟料分别替代30%、20%专用添加剂,B7组料浆扩展度为143 mm,充填体形貌为富铁绿泥石胶结假方体钙硅灰石,28 d抗压强度达2.13 MPa,较基准组低0.19 MPa,较B1提高0.26 MPa。该替代方案满足现场充填C2级强度的要求,改善流动性并显著降低了充填成本。优化的外加剂组分配比在灰砂比为1∶4条件下同样具有强度优化作用,但较灰砂比为1∶6条件下低。 相似文献
120.
为改善ADC12铝合金的耐腐蚀性能,通过超声熔铸法制备ADC12-0.5La铝合金,并利用光学显微镜、扫描电镜、能谱分析仪、硬度计、浸泡腐蚀试验和电化学工作站研究了T6热处理和稀土La改性对ADC12铝合金的微观组织、硬度和耐腐蚀性能的影响。结果表明,T6态ADC12-0.5La铝合金微观组织明显细化,α-Al尺寸减小,形貌变圆整,共晶Si相和AlFeMnSi相细化为短棒状。相比于ADC12铝合金,T6态ADC12-0.5La铝合金硬度达到117.7HV,提高了26.8%,腐蚀电流密度降低了10.7%,腐蚀电位上升了64.4%,腐蚀速率降低了54.4%,腐蚀表面平坦且光滑,表现为较轻微的晶间腐蚀。T6态ADC12-0.5La铝合金提高了腐蚀电位,Al-La-Cu稀土相阻碍了电子移动,铝合金的耐腐蚀性能得到大幅度提高。 相似文献