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51.
在.Net开发环境下,利用C++语言开发PTA生产溶剂智能优化控制软件,并介绍了软件包的设计原理和基本框架.利用广义回归神经网络建立PTA过程模型,再采用粒子群智能优化法优化过程操作参数,软件系统操作简单、用户界面友好.该软件在精对苯二甲酸(PTA)生产装置的实用效果良好,降低了醋酸和蒸汽的消耗,并为优化各工艺操作条件提供了指导,产生了一定的经济效益,具有较好的推广价值. 相似文献
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Ying-Xia Du Qiao Yang Wang-Ting Lu Qing-Yu Guan Fei-Fei Cao Geng Zhang 《Advanced functional materials》2023,33(27):2300895
Single metal atom isolated in nitrogen-doped carbon materials (M N C) are effective electrocatalysts for oxygen reduction reaction (ORR), which produces H2O2 or H2O via 2-electron or 4-electron process. However, most of M N C catalysts can only present high selectivity for one product, and the selectivity is usually regulated by complicated structure design. Herein, a carbon black-supported Co N C catalyst (CB@Co N C) is synthesized. Tunable 2-electron/4-electron behavior is realized on CB@Co-N-C by utilizing its H2O2 yield dependence on electrolyte pH and catalyst loading. In acidic media with low catalyst loading, CB@Co N C presents excellent mass activity and high selectivity for H2O2 production. In flow cell with gas diffusion electrode, a H2O2 production rate of 5.04 mol h−1 g−1 is achieved by CB@Co N C on electrolyte circulation mode, and a long-term H2O2 production of 200 h is demonstrated on electrolyte non-circulation mode. Meanwhile, CB@Co N C exhibits a dominant 4-electron ORR pathway with high activity and durability in pH neutral media with high catalyst loading. The microbial fuel cell using CB@Co N C as the cathode catalyst shows a peak power density close to that of benchmark Pt/C catalyst. 相似文献
54.
研究了Z切700 nm厚的单晶铌酸锂(LiNbO3)薄膜电畴的调控方法。利用X射线衍射仪(XRD)和原子力显微镜(AFM)对单晶LiNbO3薄膜的晶向和形貌进行了表征,并通过外加电场对单晶LiNbO3薄膜电畴进行调控。研究结果表明,该LiNbO3薄膜具有单一的(006)衍射峰,表面光滑、粗糙度低(均方根粗糙度小于1 nm)。通过外加电场和预设电畴图案对LiNbO3电畴进行精准调控,并测试了电畴稳定性。测试结果显示,调控后的电畴在温度为25~150℃内处于稳定状态,且在30 d内保持稳定,未发生弛豫现象。该研究为LiNbO3电畴工程器件的研发和应用提供了重要的技术支撑。 相似文献
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采用流动温压成型工艺制备黏结钕铁硼/锶铁氧体复合磁体,研究温压工艺参数对钕铁硼/锶铁氧体复合磁体磁性能的影响。结果表明:随着温压温度、压制时间以及保压压力的提高,黏结复合磁体的磁性能呈现先增大后减小的趋势。流动温压成型参数的选择与黏结剂有关,采用酚醛环氧树脂BPANE8200为黏结剂时,流动温压成型的最佳工艺参数:77℃加载900MPa并保压8min,复合磁体的剩磁B_r、内禀矫顽力H_(cj)以及最大磁能积(BH)max均获得最大值,即Br=522mT,Hcj=740.48kA/m,(BH)max=39.82kJ/m^3。 相似文献
57.
Huiteng Tan Lianhua Xu Hongbo Geng Xianhong Rui Chengchao Li Shaoming Huang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(21)
To further increase the energy and power densities of lithium‐ion batteries (LIBs), monoclinic Li3V2(PO4)3 attracts much attention. However, the intrinsic low electrical conductivity (2.4 × 10?7 S cm?1) and sluggish kinetics become major drawbacks that keep Li3V2(PO4)3 away from meeting its full potential in high rate performance. Recently, significant breakthroughs in electrochemical performance (e.g., rate capability and cycling stability) have been achieved by utilizing advanced nanotechnologies. The nanostructured Li3V2(PO4)3 hybrid cathodes not only improve the electrical conductivity, but also provide high electrode/electrolyte contact interfaces, favorable electron and Li+ transport properties, and good accommodation of strain upon Li+ insertion/extraction. In this Review, light is shed on recent developments in the application of 0D (nanoparticles), 1D (nanowires and nanobelts), 2D (nanoplates and nanosheets), and 3D (nanospheres) Li3V2(PO4)3 for high‐performance LIBs, especially highlighting their synthetic strategies and promising electrochemical properties. Finally, the future prospects of nanostructured Li3V2(PO4)3 cathodes are discussed. 相似文献
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59.
Xuan Peng Linxiu Cheng Xiaoyang Zhu Yanfang Geng Fengying Zhao Kandong Hu Xuan Guo Ke Deng Qingdao Zeng 《Nano Research》2018,11(11):5823-5834
The two-dimensional self-assembly behaviors of tetraphenylethylene (TPE) molecules are significant for further applications, but reports are rare. The self-assembled structures of two C2-symmetry TPE derivatives (H4TCPE and H4ETTC) possessing propeller structures and their stimulus responses to the addition of vinylpyridine derivatives were thoroughly studied with the assistance of scanning tunneling microscopy (STM) technique in combination with density functional theory (DFT) calculations. Although their chemical structures were similar, the H4TCPE and H4ETTC molecules self-assembled into closely packed lamellar and quadrilateral structures, respectively, at the 1-heptanoic acid/HOPG interface. After the addition of pyridine derivatives (DPE, PEBP-C4, and PEBP-C8), H4TCPE and H4ETTC showed different responsiveness resulting in different co-assembly structures. The results indicated that the structures of pyridine derivatives—including backbones and substituents—affected the intermolecular interactions of both H4TCPE/pyridine and H4ETTC/pyridine systems. The modification of the self-assembly behaviors of propeller-shaped H4TCPE and H4ETTC would contribute to the construction of more complex multilevel nanostructures. 相似文献
60.
Jiabin Liu Jiawei Deng Yangyang Zhu Xiaokang Geng Lifu Zhang Sang Young Jeong Dan Zhou Han Young Woo Dong Chen Feiyan Wu Lie Chen 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2208008
With the great potential of the all-polymer solar cells for large-area wearable devices, both large-area device efficiency and mechanical flexibility are very critical but attract limited attention. In this work, from the perspective of the polymer configurations, two types of terpolymer acceptors PYTX-A and PYTX-B (X = Cl or H) are developed. The configuration difference caused by the replacement of non-conjugated units results in distinct photovoltaic performance and mechanical flexibility. Benefiting from a good match between the intrinsically slow film-forming of the active materials and the technically slow film-forming of the blade-coating process, the toluene-processed large-area (1.21 cm2) binary device achieves a record efficiency of 14.70%. More importantly, a new parameter of efficiency stretchability factor (ESF) is proposed for the first time to comprehensively evaluate the overall device performance. PM6:PYTCl-A and PM6:PYTCl-B yield significantly higher ESF than PM6:PY-IT. Further blending with non-conjugated polymer donor PM6-A, the best ESF of 3.12% is achieved for PM6-A:PYTCl-A, which is among the highest comprehensive performances. 相似文献