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71.
Khang Ngoc Dinh Prof. Yu Zhang Prof. Jixin Zhu Dr. Wenping Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6437-6446
Phosphorene, generally defined as two-dimensional (2D) black phosphorus (BP) with monolayered or few-layered structure, has emerged as a promising member of the family of 2D materials. Since its discovery in 2014, extensive research has been focused on broadening its applications, covering the biological, photoelectric, and electrochemical fields, owing to the unique physicochemical and structural properties. As a single-elemental material, phosphorene has demonstrated its applicability for the preparation of efficient electrocatalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), nitrogen reduction reaction (NRR), and other electrocatalytic applications. In this Minireview, a summary of the very recent research progresses of phosphorene in electrocatalysis is offered, with a special focus on the effective synthetic strategies towards performance improvement. In the concluding section, challenges and perspectives are also discussed. 相似文献
72.
Yu Xixia Zheng Lei Li Jinfeng Wang Lu Han Jiangli Chen Huayi Zhang Xiaotao Hu Wenping 《中国科学:化学(英文版)》2019,62(2):251-255
An asymmetric anthracene derivative(4-HDPA) was designed and synthesized. With the optimization of proper scenario of fabrication process, top-contact thin film devices based on 4-HDPA exhibit mobility as high as 3.59 cm~2 V~(–1) s~(–1), while its singlecrystal devices exhibit mobility as high as 5.12 cm~2 V~(–1) s~(–1), which is higher than the symmetrical counterpart of 4-HDPA in both single-crystal and thin film devices. 相似文献
73.
Some Characterizations of Nil Ideals in BCI—algebras 总被引:2,自引:0,他引:2
51.IntrodcutionIn[1j,thenotionsofnilidealinBCI-algebrasandinlBCI-algebrawereintreduced.WeshowthatnilBCI-algebraisageneralizationofassociativeandquasi-associativeBCIalgebra([2J,[3j).lnthispaper,somecharacterizationsofnilidealsinBCI-algebraswereproved.Moreover,theBCI-algebrassatifyingO*x.=xwerediscussedandvariousproPertieswereproved.Werecallsomedefinitionsande1ementaryproperties.ThefollowingsaretrueinaBCI-al-gebra:(l)x o=x;(2)(x*y)*z=(x z) y;(3)x相似文献
74.
75.
以沥青和煤矸石为原料,经炭化、活化后获得型体活性炭材料(AC),并在此基础上进行水热晶化,研究晶化时间对复合材料中4A沸石的形成、孔结构和甲烷、氮气吸附性能的影响。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、77 K下的氮气吸附-脱附以及273 K下的CO_2吸附等温线对样品进行表征,结果表明水热晶化后,复合材料中的硅铝形成立方结构的4A沸石,出现了0.45~0.6 nm的微孔,微孔孔容增加,并伴有少量的中孔和大孔。复合材料在298 K下的甲烷(CH_4)和氮气(N_2)吸附等温线的结果表明,晶化时间6 h的复合材料AC-2的甲烷吸附量被提高至10.8 m L/g,并保持较高的CH4/N2平衡分离比(3.7)。 相似文献
76.
From Linear to Angular Isomers: Achieving Tunable Charge Transport in Single‐Crystal Indolocarbazoles Through Delicate Synergetic CH/NH⋅⋅⋅π Interactions 下载免费PDF全文
Dr. Hui Jiang Dr. Peng Hu Dr. Jun Ye Dr. Apoorva Chaturvedi Dr. Keke K. Zhang Yongxin Li Dr. Yi Long Prof. Denis Fichou Prof. Christian Kloc Prof. Wenping Hu 《Angewandte Chemie (International ed. in English)》2018,57(29):8875-8880
Weak intermolecular interaction in organic semiconducting molecular crystals plays an important role in molecular packing and electronic properties. Here, four five‐ring‐fused isomers were rationally designed and synthesized to investigate the isomeric influence of linear and angular shapes in affecting their molecular packing and resultant electronic properties. Single‐crystal field‐effect transistors showed mobility order of 5,7‐ICZ (3.61 cm2 V?1 s?1) >5,11‐ICZ (0.55 cm2 V?1 s?1) >11,12‐ICZ (ca. 10?5 cm2 V?1 s?1) and 5,12‐ICZ (ca. 10?6 cm2 V?1 s?1). Theoretical calculations based on density functional theory (DFT) and polaron transport model revealed that 5,7‐ICZ can reach higher mobilities than the others thanks to relatively higher hole transfer integral that links to stronger intermolecular interaction due to the presence of multiple NH???π and CH???π(py) interactions with energy close to common NH???N hydrogen bonds, as well as overall lower hole‐vibrational coupling owing to the absence of coupling of holes to low frequency modes due to better π conjugation. 相似文献
77.
Chunhua Liu Eunsol Park Dr. Yinghua Jin Jie Liu Yanxia Yu Prof. Dr. Wei Zhang Prof. Dr. Shengbin Lei Prof. Dr. Wenping Hu 《Angewandte Chemie (International ed. in English)》2018,57(7):1869-1873
Understanding how the constitutional dynamics of a dynamic combinatorial library (DCL) adapts to surfaces (compared to bulk solution) is of fundamental importance to the design of adaptive materials. Submolecular resolved scanning tunneling microscopy (STM) can provide detailed insights into olefin metathesis at the interface. Analysis of the distribution of products has revealed the important role of environmental pressure, reaction temperature, and substituent effects in surface‐confined olefin metathesis. We also report an unprecedented preferred deposition and assembly of linear polymers, and some specific oligomers, on the surface that are hard to obtain otherwise. 相似文献
78.
Yulu Yang Yang Tang Haomin Jiang Yongmei Chen Pingyu Wan Maohong Fan Rongrong Zhang Sana Ullah Lun Pan Ji-Jun Zou Mengmeng Lao Wenping Sun Chao Yang Gengfeng Zheng Qiling Peng Ting Wang Yonglan Luo Xuping Sun Alexander S. Konev Oleg V. Levin Panagiotis Lianos Zhuofeng Hu Zhurui Shen Qinglan Zhao Ying Wang Nadia Todorova Christos Trapalis Matthew V. Sheridan Haipeng Wang Ling Zhang Songmei Sun Wenzhong Wang Jianmin Ma 《中国化学快报》1990,30(12):2089-2109
In this roadmap, we address the development and perspectives of hydrogen evolution reaction, oxygen reduction reaction, oxygen evolution reaction, carbon dioxide reduction reaction and nitrogen reduction. 相似文献
79.
Wenping Ma Yunjie Ding Jing Yang Xing Liu Liwu Lin 《Reaction Kinetics and Catalysis Letters》2005,84(1):11-19
Summary Characterization (BET and TPD) and reaction studies were conducted with activated carbon supported iron catalysts (Fe/AC) used for the Fischer-Tropsch synthesis (FTS). The TPD study showed that there existed interactions between metals and the AC surface. Greater association of Cu and K promoters with the AC surface resulted in stronger promoter to surface interaction, which enhanced the H2 desorption ability of the Cu and K promoted Fe/AC catalyst prepared under vacuum impregnation (VI). Catalytic behavior of a Fe/AC catalyst (VI-15 Fe/2 Cu/2 K/81 AC, in parts per weight) was studied in a 1-liter slurry phase continuous stirred tank reactor. The catalyst presented moderate syngas conversion (44.3-60.6%) and high gaseous selectivity (CH4, 12.8-15.1% and C2-C4, 42.4-46.1%) under 304oC, 3.0 MPa, 1.1 L(STP)/g-cat/h, and H2/CO = 2.0 during 166 h of testing. Detectable hydrocarbons up to C18 were formed on the Fe/AC catalyst. 相似文献
80.
A mode-filtered light fiber-optic sucrose sensor was constructed from an annular column consisting of a bare optical fiber inserted into a capillary tube. A series of standard solutions with different concentrations of sucrose were measured by the sensor. The response range of the sucrose solution is 0%–60% (w/w). A linear relationship was found between the strength of the mode-filtered light and the sucrose concentration, with a correlation coefficient of 0.9994. The sensor exhibits good reproducibility and reversibility, as well as good standardized recovery for real samples. Thus, a real-time, fast, and sensitive determination method for sucrose concentration has been established. 相似文献