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921.
Hui Li Zejun Jiang Xiaolin Cao Hang Su Hua Shao Fen Jin Lufei Zheng A. M. Abd El-Aty Jing Wang 《Chromatographia》2018,81(2):359-364
922.
923.
Jun Huang Yongxiang Zhu Lianjie Zhang Ping Cai Xiaofeng Xu Junwu Chen Yong Cao 《Journal of polymer science. Part A, Polymer chemistry》2014,52(12):1652-1661
Two conjugated copolymers PADT‐DPP and PADT‐FDPP based on anthradithiophene and diketopyrrolopyrrole, with thiophene and furan as the π‐conjugated bridge, respectively, were successfully synthesized and characterized. The number‐averaged molecular weights of the two polymers are 38.7 and 30.2 kg/mol, respectively. Polymers PADT‐DPP and PADT‐FDPP exhibit broad absorption bands and their optical band gaps are 1.44 and 1.50 eV, respectively. The highest occupied molecular orbital energy level of PADT‐DPP is located at ?5.03 eV while that of PADT‐FDPP is at ?5.16 eV. In field‐effect transistors, PADT‐DPP and PADT‐FDPP displayed hole mobilities of 4.7 × 10?3 and 2.7 × 10?3 cm2/(V s), respectively. In polymer solar cells, PADT‐DPP and PADT‐FDPP showed power conversion efficiency (PCE) of 3.44% and 0.29%, respectively. Atomic force microscopy revealed that the poor efficiency of PADT‐FDPP should be related to the large two‐phase separation in its active layer. If 1,8‐diiodooctane (DIO) was used as the solvent additive, the PCE of PADT‐DPP remained almost unchanged due to very limited morphology variation. However, the addition of DIO could remarkably elevate the PCE of PADT‐FDPP to 2.62% because of the greatly improved morphology. Our results suggest that the anthradithiophene as an electron‐donating polycyclic system is useful to construct new D–A alternating copolymers for efficient polymer solar cells. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1652–1661 相似文献
924.
Tianrui Zhao Mengxue Sun Lingpeng Kong Qingwang Xue Yudan Wang Yifen Wang Afsar Khan Jianxin Cao Guiguang Cheng 《Molecules (Basel, Switzerland)》2021,26(7)
Vaccinium dunalianum Wight, usually processed as a traditional folk tea beverage, is widely distributed in the southwest of China. The present study aimed to investigate the antioxidant, α-glucosidase and pancreatic lipase inhibitory activities of V. dunalianum extract and isolate the bioactive components. In this study, the crude extract (CE) from the buds of V. dunalianum was prepared by the ultrasound-assisted extraction method in 70% methanol and then purified with macroporous resin D101 to obtain the purified extract (PM). Five fractions (Fr. A–E) were further obtained by MPLC column (RP-C18). Bioactivity assays revealed that Fr. B with 40% methanol and Fr. D with 80% methanol had better antioxidant with 0.48 ± 0.03 and 0.62 ± 0.01 nM Trolox equivalent (TE)/mg extract for DPPH, 0.87 ± 0.02 and 1.58 ± 0.02 nM TE/mg extract for FRAP, 14.42 ± 0.41 and 19.25 ± 0.23 nM TE/mg extract for ABTS, and enzyme inhibitory effects with IC50 values of 95.21 ± 2.21 and 74.55 ± 3.85 for α-glucosidase, and 142.53 ± 11.45 and 128.76 ± 13.85 µg/mL for pancreatic lipase. Multivariate analysis indicated that the TPC and TFC were positively related to the antioxidant activities. Further phytochemical purification led to the isolation of ten compounds (1–10). 6-O-Caffeoylarbutin (7) showed significant inhibitory effects on α-glucosidase and pancreatic lipase enzymes with values of 38.38 ± 1.84 and 97.56 ± 7.53 µg/mL, and had the highest antioxidant capacity compared to the other compounds. 相似文献
925.
Wang Dongliang Su Xin Fan Zongliang Wen Zhuoyu Li Ning Yang Yong 《Catalysis Surveys from Asia》2021,25(4):347-361
Catalysis Surveys from Asia - Benzene methylation over zeolite offers an alternative route to produce high-value toluene or para-xylene directly from benzene and C1 chemical sources, especially for... 相似文献
926.
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
927.
Wu Hong-Bo Liu Shang-Hao Cao Chen-Rui 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1547-1555
Journal of Thermal Analysis and Calorimetry - Free radical polymerization is an effective method for large-scale production of various olefin polymers, in which the initiator is one of the emphases... 相似文献
928.
Dr. Guang-Lan Li Bei-Bei Yang Xiao-Cun Xu Shuo Cao Prof. Yantao Shi Dr. Yang Yan Dr. Xuedan Song Prof. Ce Hao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(13):2890-2896
The development of cost-effective and durable oxygen electrocatalysts remains highly critical but challenging for energy conversion and storage devices. Herein, a novel FeNi alloy nanoparticle core encapsulated in carbon shells supported on a N-enriched graphene-like carbon matrix (denoted as FeNi@C/NG) was constructed by facile pyrolyzing the mixture of metal salts, glucose, and dicyandiamide. The in situ pyrolysis of dicyandiamide in the presence of glucose plays a significant effect on the fabrication of the porous FeNi@C/NG with a high content of doped N and large specific surface area. The optimized FeNi@C/NG catalyst displays not only a superior catalytic performance for the oxygen reduction reaction (ORR, with an onset potential of 1.0 V and half-wave potential of 0.84 V) and oxygen evolution reaction (OER, the potential at 10 mA cm−2 is 1.66 V) simultaneously in alkaline, but also outstanding long-term cycling durability. The excellent bifunctional ORR/OER electrocatalytic performance is ascribed to the synergism of the carbon shell and FeNi alloy core together with the high-content of nitrogen doped on the large specific surface area graphene-like carbon. 相似文献
929.
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
930.
Yu Na Lim Soo Kyung Chae Woongbin Yim Ji‐Yong Park Woojin Yoon Hoseop Yun Eunha Kim Seung Uk Son Hye‐Young Jang 《应用有机金属化学》2019,33(3)
The reaction of [(domppp) Pd (OAc)2] [domppp = 1,3‐bis (di‐o‐methoxyphenylphosphino)propane] and imidazolium‐functionalized carboxylic acids containing various anions (Br?, PF6?, SbF6? and BF4?) resulted in the formation of nano‐sized Pd (II) aggregates under template‐free conditions. The rate of formation of aggregates can be modulated by changing the anion, affecting the rate of polymerization of CO and olefins without fouling. Herein, we describe the analysis of Pd (II) catalysts by dynamic light scattering, atomic force microscopy, X‐ray photoelectron spectroscopy and X‐ray crystallography, and co‐ and terpolymerization results including the catalytic activity, and bulk density and molecular weight of polymers. 相似文献