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51.
52.
Ming Sun Dan Zhang Minghui Huang Jing Chen Xing Tang Chao He 《Petroleum Science and Technology》2017,35(7):674-680
This study focuses on the effects of the tetrahydrofuran-soluble fraction of direct coal liquefaction residue as a modifier to modify asphalt with formaldehyde. The properties and carbonization behavior of matrix asphalt and the modified asphalts were studied. The results indicate that the ductility properties of modified asphalts have been effectively improved. The morphology of modified asphalts without the addition of formaldehyde is a set of uniform distribution point, and it is converted from linear distribution to clustered distribution observed in fluorescence microscope images with the increase of the adding amount of formaldehyde. 相似文献
53.
Fang Liu Liangliang Yu Shiwei Lv Junjun Yao Jing Liu Xiaodong Jia 《Advanced Synthesis \u0026amp; Catalysis》2016,358(3):459-465
An unexpected reaction of cinnamylanilines was achieved through the radical cation salt‐induced aerobic oxidation of sp3 C H bonds, providing a series of 2‐arylquinolines. The mechanistic study shows that the cinnamylaniline was oxidized to an imine, which was attacked by the aniline generated through decomposition of the corresponding imine. After further intramolecular cyclization and aromatization, 2‐arylquinolines were obtained. This reaction provides a new method to construct 2‐arylquinolines from readily accessible starting materials.
54.
Hengguang Cheng Runmei Zhang Shiwei Yang Min Wang Xiaofei Zeng Lingjie Xie Chunsong Xie Jing Wu Guofu Zhong 《Advanced Synthesis \u0026amp; Catalysis》2016,358(6):970-976
By using Cinchona‐derived chiral phosphines as catalytic ligands, enantioenriched cis‐3a,8a‐hexahydropyrrolo[2,3‐b]indoles (ent‐HPIs), which are core scaffolds in a large array of biologically active natural products, can be convergently assembled under mild conditions through the silver(I)‐catalyzed asymmetric domino reaction of readily available isocyanoacetates and 2‐(2‐aminophenyl)acrylates. Various functionalities can be tolerated in the reaction, affording enantioenriched HPIs in high overall yields and good enantioselectivities (up to 92% ees).
55.
Yujie Tang Yanning Zeng Qingxia Hu Fang Huang Liqun Jin Weimin Mo Nan Sun Baoxiang Hu Zhenlu Shen Xinquan Hu Wen‐Hua Sun 《Advanced Synthesis \u0026amp; Catalysis》2016,358(16):2642-2651
A series of geometry‐constrained iminopyridyl‐palladium chlorides were synthesized and characterized. These phosphine‐free palladium complexes were explored for their catalytic activities in both Suzuki and Heck cross‐coupling reactions, achieving turnover numbers as high as 106 towards various aryl bromides, even those containing various functionalities. In addition, the influence of substituents with steric and electronic factors was reflected by the differences observed in their activities.
56.
57.
Hongqiang Li Xiaokang Ren Xuejun Lai Xingrong Zeng 《Journal of Coatings Technology and Research》2014,11(6):959-966
The effects of the type and amount of the surfactant and cosurfactant on the miniemulsion polymerization of acrylate monomers were studied, and the comparison of the kinetics between miniemulsion polymerization and conventional emulsion polymerization was discussed in the presence of reactive surfactant allyloxy nonylphenol propyl polyoxyethylene (10), ether sulfate (DNS-86), and reactive cosurfactant stearyl methacrylate (SMA). The results showed that the obtained polyacrylate miniemulsion had a high monomer conversion rate and a low coagulum fraction, which were affected little by the surfactant and cosurfactant type. When the surfactant and cosurfactant amounts were all 2 wt%, the contact angle of the prepared polyacrylate miniemulsion with DNS-86/SMA and the water absorption fraction of the latex film were 39° and 8.3 wt%, respectively. FTIR results confirmed that DNS-86 and SMA took part in the polymerization of acrylate monomers. In the miniemulsion polymerization of acrylate monomers with DNS-86/SMA, monomer droplet nucleation was the main nucleation style. 相似文献
58.
Jing Yang Bin Wang Yanping Miao Bo Sun 《Journal of Inorganic and Organometallic Polymers and Materials》2014,24(2):371-380
Two porphyrin derivatives with different substituents were investigated as dyes for the titanium dioxide (TiO2) film electrode to construct new two-compartment photoelectrochemical biofuel cells (PEBFCs). The two porphyrin derivatives were tetrakis(4-carboxyphenyl)porphyrin (TCPP) and meso-tetra(p-hydroxyphenyl)porphine (THPP). To determine how cell performance was affected by the dye with different substituents, we analyzed the photochemical and photoelectrochemical properties of the two dyes by physical characterization and photoelectrochemical experiments. The UV–Vis absorption spectra and X-ray photoelectron spectra indicated that the interactions between the dye and TiO2 decreased in the order of TCPP > THPP, which was also in accord with the results of Fourier transform infrared. In addition, TCPP and THPP were calculated using the density functional theory and the time-dependent density functional theory, and the calculation result exhibited that the radiative lifetime decreased in the order of TCPP > THPP. Compared with THPP, TCPP with longer excited-state was expected to enhance the performance of a PEBFC. We measured and compared the incident photon-to-collected electron conversion efficiency and the light-to-electrical conversion efficiency (η) of the porphyrin-sensitized photoelectrochemical biofuel cell. The photovoltaic characteristics showed the TCPP was more effective compared to the THPP, which obviously showed that the experimental results were consistent with theoretical expectation. These results revealed that the kind of the substituent for the porphyrin influenced the photovoltaic properties of the PEBFC. 相似文献
59.
本文拟在以公路工程建设为例,在借鉴前人研究经验的基础上,系统总结了工程计量在公路工程建设方面的关键作用,希望能为工程计量的进一步发展提供参考。 相似文献
60.
本文通过对陕南镇安县西凤村部分农宅调研的信息和测量数据进行的分析和总结,对当地农建设提出了科学合理的指导性意见。 相似文献