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501.
利用智能重量分析仪测试了在30℃与400℃下苯和噻吩在重油流化催化裂化(RFCC)催化剂及其主活性分子筛组分上的吸附-脱附曲线和程序升温脱附曲线,并将其与催化裂化过程中的原位降硫性能进行了关联。结果表明,噻吩在RFCC催化剂上不仅存在着物理吸附和化学吸附,还会发生低聚反应;苯与RFCC催化剂间的作用力较弱,只存在1种吸附位,400℃下苯在RFCC催化剂上以扩散过程为主,这样可减少汽油因深度裂化而造成的辛烷值损失,提高RFCC催化剂对目标产物的选择性和耐结焦性能;噻吩在RFCC催化剂上的饱和吸附量远大于苯,说明RFCC催化剂对噻吩类硫化物的吸附选择性较好。 相似文献
502.
Shimelis Admassie Fengling Zhang A.G. Manoj Mattias Svensson Mats R. Andersson Olle Ingans 《Solar Energy Materials & Solar Cells》2006,90(2):133-141
We report the photovoltaic properties of devices made using a highly conducting polymer electrode, from vapour-phase polymerized poly (3,4-ethylenedioxy) thiophene (VPP PEDOT) on glass substrate as an anode and a polyfluorene copolymer poly[2,7-(9,9-dioctyl-fluorene)-alt-5,5-(4′,7′-di-2thienyl-2′,1′3′-benzothiadiazole)] (APFO-3) mixed with [6,6]-phenyl-C61-butyric acid methylester (PCBM) in the ratio of 1:4 as the active layer. The device performance was compared with that of devices made with PEDOT-PSS on glass substrates. The surfaces of VPP PEDOT were imaged using atomic force microscopy (AFM). 相似文献
503.
Thieno[3,2‐b]thiophene Flanked Isoindigo Polymers for High Performance Ambipolar OFET Applications
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Iain Meager Mark Nikolka Bob C. Schroeder Christian B. Nielsen Miquel Planells Hugo Bronstein Joseph W. Rumer David Ian James Raja Shahid Ashraf Aditya Sadhanala Pascal Hayoz Jean‐Charles Flores Henning Sirringhaus Iain McCulloch 《Advanced functional materials》2014,24(45):7109-7115
The synthesis of a new thieno[3,2‐b]thiophene isoindigo (iITT) based monomer unit, and its subsequent incorporation into a series of alternating copolymers is reported. Copolymerisation with benzothiadiazole, bithiophene and thiophene comonomer units by palladium catalysed cross coupling gives three new narrow band gap semiconducting polymers for OFET applications. Extending the fused nature of the isoindigo core serves to further enhance molecular orbital overlap along the polymer backbones and facilitate good charge transport characteristics thus demonstrating the potential of extending the fused ring system that is attached to the isoindigo core. When used as the semiconducting channel in top‐gate/bottom‐contact OFET devices, good ambipolar properties are observed, with hole and electron mobilities up to 0.4 cm2/Vs and 0.7 cm2/Vs respectively. The three new polymers show good stability, with high temperature annealing showing an increase in the crystallinity of the polymers which corresponds directly to charge carrier mobility improvement as shown by X‐ray diffraction, atomic force microscopy and photothermal deflection spectroscopy. 相似文献
504.
Process intensification on the separation of benzene and thiophene by extractive distillation
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Jingli Han Zhigang Lei Yichun Dong Chengna Dai Biaohua Chen 《American Institute of Chemical Engineers》2015,61(12):4470-4480
The separation of benzene and trace thiophene by extractive distillation was intensified in two aspects, that is, selection of a suitable entrainer and improvement of the process. The mixture of dimethylformamide (DMF) and an ionic liquid (IL) was chosen as the entrainer. Vapor–liquid equilibrium (VLE) experiments using pure DMF and a mixed entrainer were conducted, and UNIFAC model for ILs was extended to the benzene‐thiophene‐DMF‐IL system. The results demonstrated that volatilization loss of DMF in the vapor phase was significantly reduced by adding IL. Moreover, an improved process with only four columns using a mixed entrainer was proposed. The results indicated that the improved process is more promising for decreasing energy consumption and equipment investment compared with the conventional six‐column process. The total heat duties of reboilers and condensers was decreased by 6.47% and 6.41%, respectively. The process intensification strategy may be directly extended to separate trace components of other systems. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4470–4480, 2015 相似文献
505.
Jian Li Takahiro Osasa Yasuko Hirayama Takeshi Sano Kenichiro Wakisaka Michio Matsumura 《Solar Energy Materials & Solar Cells》2007,91(8):745-750
Organic solar cells were fabricated using a new amine–bithiophene copolymer as an electron donor layer and 3,4,9,10-perylenetetracarboxyl-bis-benzimidazole (PV) as an electron acceptor layer. The amine–thiophene copolymer, poly{(9,9-dioctylfluorene-2,7-diyl)-co-[N,N′-bis(4-tert-butylphenyl)benzidine-N,N′-bis(phenylene-4,4′-diyl)]-co-(2,2′-bithiophene-5,5′-diyl)} (PF8-TPD-T2), had a glass transition temperature (Tg) at about 77 °C, and exhibited liquid crystalline states and a high hole mobility. The rigid bithiophene units in the polymer chain are probably responsible for the formation of the liquid crystalline states and the high hole mobility. A solar cell made of the PF8-TPD-T2 copolymer and PV layers showed a photocurrent density of 0.99 mA/cm2, an open-circuit voltage of 0.61 V, and an energy conversion efficiency of 0.332%. The photocurrent of the solar cells was generated at both the copolymer and PV layers, and the copolymer layer was the main contributor to photocurrent when the thickness of the polymer was about 17 nm. After annealing the solar cells at temperatures well above the glass transition temperature (Tg) of the copolymer, the photocurrent action spectra of the solar cells were broadened and the performance was improved. The changes were mostly due to the increased contribution of the PV layer to the photocurrent by the annealing. 相似文献
506.
507.
508.
苯、噻吩、N-甲基吡咯烷酮间汽液平衡的研究 总被引:1,自引:0,他引:1
介绍了利用汽液双平衡的小型平衡釜,在常压下测定苯、噻吩、N-甲基吡咯烷酮间三元体系的汽液平衡数据的实验。对此三元体系,分别用Wilson、NRTL、UNIQUAC模型对实测数据进行了关联,结果表明,3个模型均能较好地应用于此物系的汽液平衡的预测,其中Wilson方程关联结果最好。对苯/噻吩的相对挥发度与N-甲基吡咯烷酮浓度的关系曲线的分析表明,随着N-甲基吡咯烷酮浓度的增加,苯/噻吩之间的相对挥发度从1.15增加到1.35。实验结果表明,N-甲基吡咯烷酮是一种能改变苯、噻吩二元体系相对挥发度的良好萃取剂。 相似文献
509.
采用浸渍法制备了CeO_2改性的Ru/Al_2O_3、Pd/Al_2O_3加氢脱硫催化剂,分别考察了硫化态和还原态贵金属催化剂对噻吩加氢脱硫反应性能的影响,并运用XRD、TPR、TPR-S等手段对催化剂进行表征。结果表明,CeO_2的改性导致还原态Pd/Al_2O_3催化剂初始活性提高了26%,但硫化态Ru/Al_2O_3催化剂活性下降。CeO_2对Pd/Al_2O_3催化剂的改性机理在于Pd与Ce发生了强相互作用,所生成的Ce~(3+)成为了新的不同于B酸的噻吩吸附活化中心。而在Ru/Al_2O_3中,CeO_2增强了Ru-S键,导致活性中心硫空穴的减少。 相似文献
510.
Andrea Stefani Tommaso Salzillo Patrizia Romana Mussini Tiziana Benincori Massimo Innocenti Luca Pasquali Andrew C. Jones Suryakant Mishra Claudio Fontanesi 《Advanced functional materials》2024,34(2):2308948
In this paper it is experimentally demonstrated that the electron-spin/molecular-handedness interaction plays a fundamental role in the chiral recognition process. This conclusion is inferred comparing current versus potential (I–V) curves recorded using chiral electrode surfaces, which are obtained via chemisorption of an enantiopure thiophene derivative: 3,3′-bibenzothiophene core functionalized with 2,2′-bithiophene wings (BT2T4). The chiral recognition capability of these chiral-electrodes is probed via cyclic voltammetry measurements, where, Ag nanoparticles (AgNPs) capped with enantiopure BT2T4 (BT2T4@AgNP) are used as the chiral redox probe. Then, the interface handedness is explored by recording spin-polarized I–V curves in spin-dependent electrochemistry (SDE) and magnetic-conductive atomic force microscopy (mc-AFM) experiments. The quality of the interfaces is thoroughly cross-checked using X-ray photoemission spectroscopy, Raman, electrodesorption measurements, which further substantiate the metal(electrode)-sulfur(thiophene) central role in the chemisorption process. Spin-polarization values of about 15% and 30% are obtained in the case of SDE and mc-AFM experiments, respectively. 相似文献