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981.
Cao Ding Dong Yingying Tang Ying Ye Yaoyao Hu Shui Guo Zhenguo Li Xinhua 《Catalysis Surveys from Asia》2021,25(4):437-444
Catalysis Surveys from Asia - A facile and efficient electrocatalyst for hydrogen evolution reaction (HER) to produce hydrogen is very important for future energy. In this paper, amorphous... 相似文献
982.
983.
Shuang Dong Ziqin Jiang Zhen Liu Ling Chen Qiang Zhang Youli Tian Amir Sohail Muhammad Idrees Khan Hua Xiao Xiaoping Liu Yuxing Wang Honggen Li Hanyu Wu Weiwen Liu Chengxi Cao 《Electrophoresis》2020,41(16-17):1529-1538
As an effective separation tool, free-flow electrophoresis has not been used for purification of low-abundance protein in complex sample matrix. Herein, lysozyme in complex egg white matrix was chosen as the model protein for demonstrating the purification of low-content peptide via an FFE coupled with gel fitration chromatography (GFC). The crude lysozyme in egg while was first separated via free-flow zone electrophoresis (FFZE). After that, the fractions with lysozyme activity were condensed via lyophilization. Thereafter, the condensed fractions were further purified via a GFC of Sephadex G50. In all of the experiments, a special poly(acrylamide- co-acrylic acid) (P(AM-co-AA)) gel electrophoresis and a mass spectrometry were used for identification of lysozyme. The conditions of FFZE were optimized as follows: 130 μL/min sample flow rate, 4.9 mL/min background buffer of 20 mM pH 5.5 Tris-Acetic acid, 350 V, and 14 °C as well as 2 mg/mL protein content of crude sample. It was found that the purified lysozyme had the purity of 80% and high activity as compared with its crude sample with only 1.4% content and undetectable activity. The recoveries in the first and second separative steps were 65% and 82%, respectively, and the total recovery was about 53.3%. The reasons of low recovery might be induced by diffusion of lysozyme out off P(AM-co-AA) gel and co-removing of high-abundance egg ovalbumin. All these results indicated FFE could be used as alternative tool for purification of target solute with low abundance. 相似文献
984.
Yonghui Liu Huaying Gao Xiaoli Sheng Yuming Zhou Beibei Wang Xiao Sha Maolu Jin Jie Zhao Wenqi Liu 《应用有机金属化学》2019,33(11)
In this work, a series of novel acidic polymerized ionic liquids were used as heterogeneous catalyst for alkylation of o‐Xylene with styrene. And the effect of the amount of initiator and the type of acid used for ion exchange on catalyst structure and the catalytic performance of catalysts for alkylation were studied thoroughly. The experiment results show: when the percentage of the amount of initiator in the total material is 3%, the polymerized ionic liquid catalyst MPM‐SO3H‐[C3V][SO3CF3] has the most uniform with a specific surface area of 97.30 m2/g and a pore volume of 0.35 cm3/g. Benefiting from the unique structure features, MPM‐SO3H‐[C3V][SO3CF3] manifested an excellent catalytic performance for alkylation of o‐Xylene with styrene, along with the conversion of styrene was 96.8% and the yield of 1‐Phenyl‐1‐ortho‐xylene ethane was 94.7%. Therefore, this work provides a novel reference to the synthesis of polymerized ionic liquids and clearly explains the advantage of novel acidic polymerized ionic liquids on alkylation. 相似文献
985.
Science China Mathematics - By mapping the homogeneous coordinates of two points in space to the Plücker coordinates of the line they determine, any transformation of type SL(4) upon points in... 相似文献
986.
Ultrathin Mn Doped Ni-MOF Nanosheet Array for Highly Capacitive and Stable Asymmetric Supercapacitor
Dengchao Zheng Hao Wen Xun Sun Xin Guan Jie Zhang Wenli Tian Hao Feng Dr. Hongjing Wang Prof. Yadong Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17149-17155
In this study, we demonstrate that an Mn-doped ultrathin Ni-MOF nanosheet array on nickel foam (Mn0.1-Ni-MOF/NF) serves as a highly capacitive and stable supercapacitor positive electrode. The Mn0.1-Ni-MOF/NF shows an areal capacity of 6.48 C cm−2 (specific capacity C: 1178 C g−1) at 2 mA cm−2 in 6.0 m KOH, outperforming most reported MOF-based materials. More importantly, it possesses excellent cycle stability to maintain 80.6 % capacity after 5000 cycles. An asymmetric supercapacitor device utilizing Mn0.1-Ni-MOF/NF as the positive electrode and activated carbon as the negative electrode attains a high energy density of 39.6 Wh kg−1 at 143.8 Wkg−1 power density with a capacitance retention of 83.6 % after 5000 cycles. 相似文献
987.
Pengcheng Li Jie Dai Yi Xu Qichao Ran Yi Gu 《Journal of polymer science. Part A, Polymer chemistry》2019,57(14):1587-1592
A difunctional benzoxazine (coPh‐apa) with a conjugated alkyne group is synthesized by the oxidative coupling reaction from a monocycle‐benzoxazine (Ph‐apa) containing an alkyne group. A model compound, 1,4‐diphenylbutadiyne (coPa), is used to study the curing reaction process of coPh‐apa by DSC, Fourier transform infrared spectroscopy, and 13C NMR, and the results suggest that the conjugated alkyne groups are involved in the crosslinking reaction via the trimerization reaction of the conjugated alkynyl groups and the Diels–Alder reaction. Furthermore, thermal properties of the polybenzoxazine are studied by dynamic thermomechanical analysis and thermogravimetric analysis. A glass‐transition temperature (Tgs) of as high as 412 °C and a char yield of 75.6% at 800 °C under nitrogen are obtained with the aid of the conjugated alkyne groups. Its excellent heat resistance dominates most thermosetting resins and will serve for heat shields. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1587–1592 相似文献
988.
Jie Wang Denan Li Honggui Yang Shufan Yao Prof. Qianqian Zhu Prof. Masahiro Sadakane Prof. Yanshuo Li Prof. Wataru Ueda Prof. Zhenxin Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(41):e202200618
Zeolitic octahedral metal oxides are inorganic crystalline microporous materials with adsorption and redox properties. New ϵ-Keggin nickel molybdate–based zeolitic octahedral metal oxides have been synthesized. 31P NMR spectroscopy shows that reduction of MoVI-based molybdates forms an ϵ-Keggin polyoxometalate that immediately transfers to the solid phase. Investigation of the formation process indicates that a low Ni concentration, insoluble reducing agent, and long synthesis time are the critical factors for obtaining the zeolite octahedral metal oxides rather than the ϵ-Keggin polyoxometalate molecule. The synthesized zeolitic nickel molybdate with Na+ is used as the adsorbent, which effectively separates C2 hydrocarbon mixtures. 相似文献
989.
Dr. Xiaoming Jie Dr. Qiu Sun Dr. Constantin G. Daniliuc Robert Knitsch Prof. Dr. Michael Ryan Hansen Prof. Dr. Hellmut Eckert Dr. Gerald Kehr Prof. Dr. Gerhard Erker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1269-1273
The active six-membered cyclo-FLP 6 undergoes a rapid P/B addition reaction to carbon dioxide. At elevated temperature, the resulting heterobicyclo[2.2.2]octane derived product 7 undergoes ring opening and equilibrates with the cyclotetramer (7)4 . In the large macrocyclic structure, four monomeric six-membered cyclo-FLP units are connected by four CO2 molecules to form the supramolecular ring system. The P/B cyclo-FLP 6 undergoes a variety of additional cycloaddition reactions. 相似文献
990.
A variety of heterobiaryl compounds have been synthesized by the Suzuki‐Miyaura coupling reactions of heteroaryl halides with potassium aryltrifluoroborates. Pd (OAc)2 was found to be highly efficient for the Suzuki‐Miyaura coupling reactions of various heteroaryl halides with potassium aryltrifluoroborates in aqueous systems, delivering the corresponding heterobiaryl compounds in good to excellent yields. 相似文献