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51.
This study is focused on the kinetic characteristics of photocatalytic degradation of gaseous organic compounds on modified titanium dioxide/activated carbon composite photocatalyst(MTA).The MTA,which co-doping with iron(Fe) and nitrogen(N),was synthesized by a sol-gel method,and its photocatalytic performance was investigated under different reaction conditions.The experimental data obtained were tested by the zero,first and second order kinetic model,and the factors affecting the kinetic model were analyzed.It was clearly demonstrated that the experimental data of toluene and acetone on MTA fit quite well with second order kinetic model equation,but the experimental data of formaldehyde fits well with zero order kinetic model equation. 相似文献
52.
Qingshan Yuan Zunju Zhang Lei Li Samira Agbolaghi Saina Mousavi 《Polymer International》2020,69(9):833-846
Morphological and photovoltaic stabilities of poly(3‐hexylthiophene) (P3HT):phenyl‐C61‐butyric acid methyl ester (PC71BM) solar cells were investigated in pristine and modified states. To this end, four types of patterned/assembled nanostructures, namely reduced graphene oxide (rGO)‐g‐poly(3‐dodecylthiophene)/P3HT patched‐like pattern, rGO–polythiophene/P3HT/PC71BM nanofiber, rGO‐g‐P3HT/P3HT cake‐like pattern and supra(polyaniline (PANI)‐g‐rGO/P3HT), were designed on the basis of rGO and various conjugated polymers. Intermediately covered rGO nanosheets by P3HT crystals (supra(PANI‐g‐rGO/P3HT)) performed better than sparsely (patched‐like pattern) and fully (cake‐like pattern) covered ones in P3HT:PC71BM solar cell systems. Supra(PANI‐g‐rGO/P3HT) nanohybrids largely phase‐separated in active layers (root mean square = 0.88 nm) and also led to the highest performance (power conversion efficiency of 5.74%). The photovoltaic characteristics demonstrated decreasing trends during air aging for all devices, but with distinct slopes. The steepest decreasing plots were obtained for the unmodified P3HT:PC71BM devices (from 1.77% to 0.28%). The two supramolecules with the most ordered structures, that is, cake‐like pattern (10.12 mA cm?2, 51%, 0.58 V, 2.2 × 10?6 cm2 V?1 s?1, 4.3 × 10?5 cm2 V?1 s?1, 0.69 nm and 2.99%) and supra(PANI‐g‐rGO/P3HT) (12.51 mA cm?2, 57%, 0.63 V, 1.2 × 10?5 cm2 V?1 s?1, 3.4 × 10?4 cm2 V?1 s?1, 0.82 nm and 4.49%), strongly retained morphological and photovoltaic stabilities in P3HT:PC71BM devices after 1 month of air aging. According to the morphological, optical, photovoltaic and electrochemical results, the supra(PANI‐g‐rGO/P3HT) nanohybrid was the best candidate for stabilizing P3HT:PC71BM solar cells. © 2020 Society of Chemical Industry 相似文献
53.
电化学储能器件的性能很大程度上决定于其电极材料。碳材料具有来源广泛、化学稳定性好、易于调控、环境友好等优点,被广泛应用于各类能量存储系统,但仍存在能量密度低、倍率性能差等问题。本文从碳材料孔结构调控、杂原子掺杂、与金属氧化物复合三个角度,综述了构建高性能碳基储能材料的设计合成策略,介绍了其在锂/钠离子二次电池、超级电容器等领域的研究进展,对几种方法策略的优缺点进行了总结,并对未来的研究方向进行了展望。本文对高性能碳基储能电极材料的设计开发具有积极意义。 相似文献
54.
基于C4AF可以提高水泥基材料的抗蚀性,以高铁低钙水泥熟料为研究对象,掺入不同含量的CuO,通过对熟料及其水化产物进行X射线衍射(XRD)、水化热、抗压强度、非蒸发水含量和固化氯离子能力等测试,探究Cu2+对高铁低钙水泥熟料水化性能与氯离子吸附固化能力的影响.结果发现,适量CuO的掺入促进了高铁低钙水泥熟料中C4AF的生成,降低了熟料液相的粘度,有利于C3S的晶粒生长,有利于提高高铁低钙水泥熟料的水化活性和固化氯离子能力,最佳掺量为0.2 wt%. 相似文献
55.
喷射反应器是一种重要的化工过程强化设备,可有效强化传质与传热过程、加快反应速率、提高反应产率,近年来在多个领域得到应用。本文对两种典型喷射反应器的结构及其工作原理进行了描述,系统地分析了各操作参数和结构参数对气体吸入量和气泡直径的影响规律,指出研究气体吸入和气泡破碎两种机制的必要性。对采用计算流体力学方法模拟喷射反应器内气液两相流进行了分析,指出Mixture模型适合研究气体吸入量,无法准确描述气泡运动和破碎这两个重要过程,提出采用计算流体力学与群体平衡模型结合的方法进行模拟,关键在于建立适合喷射反应器的气泡破碎频率模型。另外,结合工业应用的实际情况,强调了加入催化剂颗粒相的多相流分析对于指导工业应用的重要意义。 相似文献
56.
针对小直径水力旋流器,设计了不同内置挡板式的溢流管和底流管,实验研究了新型出口挡板结构对水力旋流器分离性能的影响。研究结果表明:内置挡板溢流管适用于处理量较大的工况,与传统溢流管相比,分离效率略有降低,但在高流量下其压降的降低幅度可达11.11%,挡板宜采用相对较窄、较短、三块120°间隔设计方式;底流管内置挡板采用十字交叉结构可稳定内旋流,使分离效率最大可提高5.96%;新型内置挡板的溢流口与底流口相耦合,可同时实现提高分离效率和降低压降的目标。此外,在相同情况下,发现溢流管内置挡板可消除水力旋流器内部的“空气柱”,据此推断“空气柱”并非由内部空气形成,而是其内部负压中心形成的某种湍流程度较高的强制旋流涡。 相似文献
57.
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59.
The electrochemical properties of spinel compound LiNi0.5Mn1.2Ti0.3O4 were investigated in this study.The chemicals LiAc·2H2O,Mn(Ac)2·2H2O,Ni(Ac)2·4H2O,and Ti(OCH3)4 were used to synthesize LiNi0.5Mn1.2Ti0.3O4 by a simple sol-gel method.The discharge capacity of the sample reached 134 mAh/g at a current rate of 0.1C.The first and fifth cycle voltammogram almost overlapped,which showed that the prepared sample LiNi0.5Mn1.2Ti0.3O4 had excellent good cycle performance.There were two oxidation peaks at 4.21 V and 4.86 V,and two reduction peaks at 4.55 V and 3.88 V in the cycle voltammogram,respectively.By electrochemical impedance spectroscopy and its fitted result,the lithium ion diffusion coefficient was measured to be approximately 7.76 × 10?11 cm2/s. 相似文献
60.
Degradation behavior of ZnO‐glass fiber‐unsaturated polyester composite under exposure to a metal halide lamp is investigated by means of DSC and FTIR. The FTIR results show that the UV photons can increase the carbonyl group on the surface, but ZnO can decrease the carbonyl content and further contribute to the breaking of single bond of carbon to oxygen on the surface. All of the results indicate that for pure unsaturated polyester under the UV exposure in air, the major reaction is photo‐initiated oxidation, whereas for the composites with ZnO, decarbonylation is the major effect. In addition, when the content of ZnO is not higher than 4 wt %, the composites are still transparent, and its effects on the crosslinking process and thermal stability are insignificant. Thus, ZnO can be used as a stabilizer of unsaturated polyester for the glass fiber reinforced polymer industry. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献